Difference between revisions of "Paper - Contributions to the embryology of the marsupialia 4"

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Introduction
 
Introduction
  
[[Paper - Contributions to the embryology of the marsupialia 4-1|Chapter I.  -  Critical Review of Previous Observations on the Early Development of Marsupialia]]
+
# [[Paper - Contributions to the embryology of the marsupialia 4-1|Critical Review of Previous Observations on the Early Development of Marsupialia]]
 
+
# [[Paper - Contributions to the embryology of the marsupialia 4-2|The Ovum of Dasyurus]]
[[Paper - Contributions to the embryology of the marsupialia 4-2|Chapter II.  -  The Ovum of Dasyurus]]
+
## Structure of Ovarian Ovum
 
+
## Maturation and Ovulation
1. Structure of Ovarian Ovum . . .11
+
## Secondary Egg-membranes
 
+
## Uterine Ovum
2. Maturation and Ovulation . . .21
+
# [[Paper - Contributions to the embryology of the marsupialia 4-3|Cleavage and Formation of Blastocyst]]
 
+
## Cleavage
3. Secondary Egg-membranes . . .23
+
## Formation of Blastocyst
 
+
# [[Paper - Contributions to the embryology of the marsupialia 4-4|Growth of Blastocyst and Differentiation OP THE Embryonal Ectoderm and the Entoderm]]
4. Uterine Ovum . . . .25
+
## Growth of Blastocyst
 
+
## Differentiation of the Embryonal Ectoderm and the Entoderm
[[Paper - Contributions to the embryology of the marsupialia 4-3|Chapter III.  -  Cleavage and Formation of Blastocyst]]
+
## Establishment of the Definitive Embryonal Area
 
+
## Summary
1. Cleavage . . . . .28
+
# [[Paper - Contributions to the embryology of the marsupialia 4-5|Chapter V.  -  Some Early Stages of Perameles and Macropus]]
 
+
# [[Paper - Contributions to the embryology of the marsupialia 4-6|Chapter VI.  -  General Summary and Conclusions]]
2. Formation of Blastocyst . . .37
+
# [[Paper - Contributions to the embryology of the marsupialia 4-7|Chapter VII. -  The Early Ontogeny of the Mammalia in the Light of the Foregoing Observations]]  
 
+
## The Early Development of the Prototheria
[[Paper - Contributions to the embryology of the marsupialia 4-4|Chapter IV.  -  Growth of Blastocyst and Differentiation OP THE Embryonal Ectoderm and the Entoderm]]
+
## The Early Development of the Metatheria and Eutheria
 
+
## The Entypic Condition of the Eutherian Blastocyst
1. Growth of Blastocyst . . .43
 
 
 
 
 
2. Differentiation of the Embryonal Ectoderm and  
 
 
 
the Entoderm . . . .52
 
 
 
3. Establishment of the Definitive Embryonal Area 65
 
 
 
4. Summary . . . .72
 
 
 
[[Paper - Contributions to the embryology of the marsupialia 4-5|Chapter V.  -  Some Early Stages of Perameles and Macropus]]
 
 
 
[[Paper - Contributions to the embryology of the marsupialia 4-6|Chapter VI.  -  General Summary and Conclusions]]
 
 
 
[[Paper - Contributions to the embryology of the marsupialia 4-7|Chapter VII. -  The Early Ontogeny of the Mammalia in the Light of the Foregoing Observations]]  
 
 
 
1 . The Early Development of the Prototheria . 86
 
 
 
2. The Early Development of the Metatheria and Eutheria . . . .96
 
 
 
3. The Entypic Condition of the Eutherian Blastocyst .... Ill
 
 
 
Addendum ...... 121
 
 
 
List op References ..... 122
 
 
 
[[Paper - Contributions to the embryology of the marsupialia 4-Plates|Explanation of Plates]]
 
  
 +
* Addendum
 +
* List op References
 +
* [[Paper - Contributions to the embryology of the marsupialia 4-Plates|Explanation of Plates]]
  
 
==Introduction==
 
==Introduction==
  
:"In mammalian embiyology very many sm-prises are yet in store for us" ([[Embryology History - Ambrosius Hubrecht|Hubrecht]], 08).
+
:"In mammalian embiyology very many surprises are yet in store for us" ([[Embryology History - Ambrosius Hubrecht|Hubrecht]], 08).  
 
 
The present contribution contains an account of the nrincipal results and conclusions at which I have arrived after a
 
somewhat protracted and much interrupted study of an
 
extensive collection of early developmental stages of Marsupials, ranging from the fertilised egg to the blastocyst in which
 
the two primary germ layers are definitely established. I
 
believe I nm now able to give for the first time an account of
 
early Marsupial ontogeny, based on the examination of an
 
adequate material, and both consistent in itself and with Avhat
 
we know of the early development in the other two Mammalian sub-classes. The material at my disposal was obtained
 
during my tenure of office in the University of Sydney, and
 
with the aid of grants from the Royal Society and of a George
 
Heriot Research Fellowship. It represents the proceeds of
 
some eight years’ collecting, and comprises a fairly complete
 
series of stages of the native cat (Dasyurus viverrinus),
 
together with a few early stages of other Marsupials, notably
 
Perameles and Macropus.
 
 
 
Dasyurus proved in many ways a convenient subject for
 
embryological purposes. It can readily be trapped in many
 
WELLCOME NeAv South Wales; it lives and breeds fairly well
 
 
 
LIBF’^R’in captb ity, and though always somewhat intractable, it can,
 
its size, be easily handled, and so may be subjected
 
 
 
 
 
Coll.
 
 
 
Call
 
 
 
No.  
 
  
  
welMOWiW:t<
+
The present contribution contains an account of the nrincipal results and conclusions at which I have arrived after a somewhat protracted and much interrupted study of an extensive collection of early developmental stages of Marsupials, ranging from the fertilised egg to the blastocyst in which the two primary germ layers are definitely established. I believe I nm now able to give for the first time an account of early Marsupial ontogeny, based on the examination of an adequate material, and both consistent in itself and with Avhat we know of the early development in the other two Mammalian sub-classes. The material at my disposal was obtained during my tenure of office in the University of Sydney, and with the aid of grants from the Royal Society and of a George Heriot Research Fellowship. It represents the proceeds of some eight years collecting, and comprises a fairly complete series of stages of the native cat (Dasyurus viverrinus), together with a few early stages of other Marsupials, notably Perameles and Macropus.
  
QL
 
  
 +
Dasyurus proved in many ways a convenient subject for embryological purposes. It can readily be trapped in many places in New South Wales; it lives and breeds fairly well in captivity, and though always somewhat intractable, it can, owing to its size, be easily handled, and so may be subjected if necessary to daily exarainationd But it lias this great disadvantage, which it apparently shares with other Marsupials, that a very variable period intervenes between coitus and ovulation. As a consequence, the obtaining of any desired cleavage or early blastocyst stage is largely a matter of chance.^ It is true that the changes which take place in the pouch, in correlation with ovulation and the events connected therewith, do afford in the case of late pregnant females some indication of the stage of development likely to be met with, but these changes are at first of too indefinite a character to be of much service beyond indicating that ovulation may have taken place.
  
  
 +
Dasyurus breeds but once a year, the breeding season extending over the winter months - May to August. One remarkable featui'e in the reproduction of Dasyurus, to which I have directed attention in a previous paper (Hill, ’00), may be again referred to here, and that is the fact that there is no correlation between the number of ova shed during ovulation and the accommodation available in the pouch. The normal number of teats present in the latter is six, though the pi-esence of one or two supernumerary teats is not uncommon; the number of ova shed at one period is, as a rule, far in excess of the teat number. I have, for example, several records of the occurrence of from twenty to twenty-five eggs, two of twenty-eight, one of thirty, and one of as many as thirty-five! (twenty-three normal blastocysts and twelve abnormal), there can be little doubt that Dasyurus, like various other Marsupials (e.g. Perameles, Macropus, etc.), has suffered a progressive reduction in the number of young reared, but even making due allowance for that, the excess in production of ova over requii’eraents would still be remarkable enough. Whether this over-production is to be correlated in any way with the occurrence of abnormalities during early development or not, the fact remains that cleavage abnormalities are quite frequently met with in Dasyurus.
  
THE EARLY DEVELOPMENT OP THE MARSUPIALIA. 3
 
  
if iiecBSsary to daily exarainationd But it lias this great disadvantage, which it apparently shares with other Marsupials,  
+
* Perameles, on the other hand, though quite common in many parts of tlie State, is hy no means such a convenient type. It is much less easily trapped than Dasyurus, does not live nearly so well in captivity, and is pai'ticularly difficiilt to handle. I have to thank Mr. D. G. Stead, now of the Department of Fisheries, Sydney, for first directing my attention to the breeding habits of Dasyurus, and also for providing me with the first female from which I obtained segmenting eggs.
that a very variable period intervenes between coitus and
 
ovulation. As a consequence, the obtaining of any desired
 
cleavage or early blastocyst stage is largely a matter of
 
chance.^ It is true that the changes which take place in the
 
pouch, in correlation with ovulation and the events connected
 
therewith, do afford in the case of late pregnant females some
 
indication of the stage of development likely to be met with,  
 
but these changes are at first of too indefinite a character to  
 
be of much service beyond indicating that ovulation may have
 
taken place.  
 
  
Dasyurus breeds but once a year, the breeding season
+
* For example, I obtained unsegmented ova from the uteri, four, five, six, seven and eight days after coitus, 2-celled eggs six and seven days after, 4-celled eggs eleven and eighteen days after. In one case the young were bom eight days after the last observed act of coitus, in another sixteen days after, and in yet another twenty days after.
extending over the winter months  -  May to August. One
 
remarkable featui'e in the reproduction of Dasyurus, to which
 
I have directed attention in a previous paper (Hill, ’00), may
 
be again referred to here, and that is the fact that there is no
 
correlation between the number of ova shed during ovulation
 
and the accommodation available in the pouch. The normal
 
number of teats present in the latter is six, though the
 
pi-esence of one or two supernumerary teats is not uncommon;
 
the number of ova shed at one period is, as a rule, far in  
 
excess of the teat number. I have, for example, several
 
records of the occurrence of from twenty to twenty-five eggs,
 
two of twenty-eight, one of thirty, and one of as many as
 
thirty-five! (twenty-three normal blastocysts and twelve
 
  
^ Perameles, on the other hand, though quite common in many parts
 
of tlie State, is hy no means such a convenient type. It is much less
 
easily trapped than Dasyurus, does not live nearly so well in captivity,
 
and is pai'ticularly difficiilt to handle. I have to thank Mr. D. G. Stead,
 
now of the Department of Fisheries, Sydney, for first directing my
 
attention to the breeding habits of Dasyurus, and also for providing
 
me with the first female from which I obtained segmenting eggs.
 
  
^ For example, I obtained unsegmented ova from the uteri, four, five,
 
six, seven and eight days after coitus, 2-celled eggs six and seven
 
days after, 4-celled eggs eleven and eighteen days after. In one case
 
the young were bom eight days after the last observed act of coitus,
 
in another sixteen days after, and in yet another twenty days after.
 
  
  
4
+
===Technique===
 +
As fixatives, I have employed for ovaries the fluids of Hermann, Flemming, Ohlmacher, and Zenker; for ova and early blastocysts, Hermann, Flemming, Perenyi, and especially picro-nitro-osmic acid (picro-nitric acid [Mayer] 96 C.C., 1 per cent, osmic acid 2 c.c., glac. acetic acid 2 c.c.) ; for later blastocysts, the last-named fluid especiall}'^ also picro-corrosive-acetic aud corrosive-acetic.
  
  
J. P. HILL.  
+
To facilitate the handling of ova and early blastocysts during embedding, I found it convenient to attach each specimen separately to a small square of pig’s foetal membrane by means of a dilute solution of photoxylin (1 to 2 per cent.), Orientation of the specimen was then easily effected during final embedding, under the low power of the microscope. The larger blastocysts were double-embedded in photoxylin and paraffin, the cavity of the blastocyst being tensely filled with the photoxylin solution by means of a hypodermic syringe fitted with a fine needle.
  
  
abnormal), there can be little doubt that Dasyurus, like
+
For the staining of sections, Heidenhain's iron-htematoxylin method proved the most satisfactory, and was almost exclusively employed. Entire portions of the blastocyst wall were stained either with Ehrlich's or Delafield's haematoxylin.
various other Marsupials (e.g. Perameles, Macropus, etc.),
 
has suffered a progressive reduction in the number of young
 
reared, but even making due allowance for that, the excess
 
in production of ova over requii’eraents would still be remarkable enough. Whether this over-production is to be correlated
 
in any way with the occurrence of abnormalities during early
 
development or not, the fact remains that cleavage abnormalities are quite frequently met with in Dasyurus.  
 
  
Technique.  -  As fixatives, I have employed for ovaries
 
the fluids of Hermann, Flemming, Ohlmacher, and Zenker;
 
for ova and early blastocysts, Hermann, Flemming, Perenyi,
 
and especially picro-nitro-osmic acid (picro-nitric acid [Mayer]
 
96 C.C., 1 per cent, osmic acid 2 c.c., glac. acetic acid 2 c.c.) ;
 
for later blastocysts, the last-named fluid especiall}'^ also
 
picro-corrosive-acetic aud corrosive-acetic.
 
  
To facilitate the handling of ova and early blastocysts
+
I am much indebted to Mr. L. Scbaeffer, of the Anatomical Department of the University of Sydney, and to Mr. F. Pittock, of the Zoological Department, University College, for invaluable assistance in the preparation of the photomicrographs reproduced on Plates 1 - 5, and also to Mr. A. Cronin, of Sydney, and Miss M. Rhodes, for the drawings from their respective pencils reproduced on Plates 6 aud 7. To Miss V. Sheffield I am indebted for tlie original of fig. 63.
during embedding, I found it convenient to attach each
 
specimen separately to a small square of pig’s foetal membrane
 
by means of a dilute solution of photoxylin (1 to 2 per cent.),  
 
Orientation of the specimen was then easily effected during
 
final embedding, under the low power of the microscope. The
 
larger blastocysts were double-embedded in photoxylin and  
 
paraffin, the cavity of the blastocyst being tensely filled with
 
the photoxylin solution by means of a hypodermic syringe
 
fitted with a fine needle.  
 
  
For the staining of sections, Heidenhain's iron-htematoxylin method proved the most satisfactory, and was almost  exclusively employed. Entire portions of the blastocyst wall were stained either with Ehrlich's or Delafield's haematoxylin.  
+
To my friend Dr. F. P. Sandes, Sydney, I am indebted for kind help in the revision of certain parts of the manuscript.
  
I am much indebted to Mr. L. Scbaeffer, of the Anatomical Department of the University of Sydney, and to Mr. F. Pittock, of the Zoological Department, University College, for invaluable assistance in the preparation of the photomicrographs reproduced on Plates 1 - 5, and also to Mr. A. Cronin, of Sydney, and Miss M. Rhodes, for the drawings from their respective pencils reproduced on Plates 6 aud 7. To Miss V. Sheffield I am indebted for tlie original of fig. 63.
 
  
To my friend Dr. F. P. Sandes, Sydney, I am indebted for  kind help in the revision of certain parts of the manuscript.
+
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Hill JP. The Early Development of the Marsupialia, with Special Reference to the Native Cat (Dasyurus Viverrinus). (1910) Quart. J. Micro. Sci. 56(1): 1-134.

  Contents: 1 Review of Previous Observations | 2 The Ovum of Dasyurus | 3 Cleavage and Blastocyst | 4 Blastocyst Growth Ectoderm Entoderm | 5 Early Stages of Perameles and Macropus | 6 Summary and Conclusions | 7 Early Mammalia Ontogeny | Explanation of Plates
Online Editor  
Eastern quoll
Eastern quoll
Mark Hill.jpg
This historic 1910 paper by James Peter Hill describes marsupial development in the native cat (Dasyurus Viverrinus)



Note that native cat, eastern native cat, are historic names for the eastern quoll Dasyurus Viverrinus (D. viverrinus). The eastern quoll is a medium-sized carnivorous marsupial native to Australia.

  • Dasyurus - "hairy tail"

dasyurid

Modern Notes:

Australian Animal: echidna | kangaroo | koala | platypus | possum | Category:Echidna | Category:Kangaroo | Category:Koala | Category:Platypus | Category:Possum | Category:Marsupial | Category:Monotreme | Development Timetable | K12
Historic Australian Animal  
Historic Embryology: 1834 Early Kangaroo | 1880 Platypus Cochlea | 1887 Monotremata and Marsupialia | 1910 Eastern Quoll | 1915 The Monotreme Skull | 1939 Early Echidna

The Hill Collection contains much histology of echidna and platypus embryonic development.

Embryology History | Historic Disclaimer

Other Marsupials  
Monito del Monte Development | Opossum Development
Historic Disclaimer - information about historic embryology pages 
Mark Hill.jpg
Pages where the terms "Historic" (textbooks, papers, people, recommendations) appear on this site, and sections within pages where this disclaimer appears, indicate that the content and scientific understanding are specific to the time of publication. This means that while some scientific descriptions are still accurate, the terminology and interpretation of the developmental mechanisms reflect the understanding at the time of original publication and those of the preceding periods, these terms, interpretations and recommendations may not reflect our current scientific understanding.     (More? Embryology History | Historic Embryology Papers)

The Early Development of the Marsupialia, with Special Reference to the Native Cat (Dasyurus Viverrinus)

James Peter Hill
James Peter Hill

(Contributions to the Embryology of the Marsupialia, IV.)


By

J. P. Hill, H.Sc.,

Jodrell Professor of Zoology and Comparative Anatomy, University of London, University College.


With Plates 1-9 and 2 Text-figs.


Table of Contents

Introduction

  1. Critical Review of Previous Observations on the Early Development of Marsupialia
  2. The Ovum of Dasyurus
    1. Structure of Ovarian Ovum
    2. Maturation and Ovulation
    3. Secondary Egg-membranes
    4. Uterine Ovum
  3. Cleavage and Formation of Blastocyst
    1. Cleavage
    2. Formation of Blastocyst
  4. Growth of Blastocyst and Differentiation OP THE Embryonal Ectoderm and the Entoderm
    1. Growth of Blastocyst
    2. Differentiation of the Embryonal Ectoderm and the Entoderm
    3. Establishment of the Definitive Embryonal Area
    4. Summary
  5. Chapter V. - Some Early Stages of Perameles and Macropus
  6. Chapter VI. - General Summary and Conclusions
  7. Chapter VII. - The Early Ontogeny of the Mammalia in the Light of the Foregoing Observations
    1. The Early Development of the Prototheria
    2. The Early Development of the Metatheria and Eutheria
    3. The Entypic Condition of the Eutherian Blastocyst

Introduction

"In mammalian embiyology very many surprises are yet in store for us" (Hubrecht, 08).


The present contribution contains an account of the nrincipal results and conclusions at which I have arrived after a somewhat protracted and much interrupted study of an extensive collection of early developmental stages of Marsupials, ranging from the fertilised egg to the blastocyst in which the two primary germ layers are definitely established. I believe I nm now able to give for the first time an account of early Marsupial ontogeny, based on the examination of an adequate material, and both consistent in itself and with Avhat we know of the early development in the other two Mammalian sub-classes. The material at my disposal was obtained during my tenure of office in the University of Sydney, and with the aid of grants from the Royal Society and of a George Heriot Research Fellowship. It represents the proceeds of some eight years collecting, and comprises a fairly complete series of stages of the native cat (Dasyurus viverrinus), together with a few early stages of other Marsupials, notably Perameles and Macropus.


Dasyurus proved in many ways a convenient subject for embryological purposes. It can readily be trapped in many places in New South Wales; it lives and breeds fairly well in captivity, and though always somewhat intractable, it can, owing to its size, be easily handled, and so may be subjected if necessary to daily exarainationd But it lias this great disadvantage, which it apparently shares with other Marsupials, that a very variable period intervenes between coitus and ovulation. As a consequence, the obtaining of any desired cleavage or early blastocyst stage is largely a matter of chance.^ It is true that the changes which take place in the pouch, in correlation with ovulation and the events connected therewith, do afford in the case of late pregnant females some indication of the stage of development likely to be met with, but these changes are at first of too indefinite a character to be of much service beyond indicating that ovulation may have taken place.


Dasyurus breeds but once a year, the breeding season extending over the winter months - May to August. One remarkable featui'e in the reproduction of Dasyurus, to which I have directed attention in a previous paper (Hill, ’00), may be again referred to here, and that is the fact that there is no correlation between the number of ova shed during ovulation and the accommodation available in the pouch. The normal number of teats present in the latter is six, though the pi-esence of one or two supernumerary teats is not uncommon; the number of ova shed at one period is, as a rule, far in excess of the teat number. I have, for example, several records of the occurrence of from twenty to twenty-five eggs, two of twenty-eight, one of thirty, and one of as many as thirty-five! (twenty-three normal blastocysts and twelve abnormal), there can be little doubt that Dasyurus, like various other Marsupials (e.g. Perameles, Macropus, etc.), has suffered a progressive reduction in the number of young reared, but even making due allowance for that, the excess in production of ova over requii’eraents would still be remarkable enough. Whether this over-production is to be correlated in any way with the occurrence of abnormalities during early development or not, the fact remains that cleavage abnormalities are quite frequently met with in Dasyurus.


  • Perameles, on the other hand, though quite common in many parts of tlie State, is hy no means such a convenient type. It is much less easily trapped than Dasyurus, does not live nearly so well in captivity, and is pai'ticularly difficiilt to handle. I have to thank Mr. D. G. Stead, now of the Department of Fisheries, Sydney, for first directing my attention to the breeding habits of Dasyurus, and also for providing me with the first female from which I obtained segmenting eggs.
  • For example, I obtained unsegmented ova from the uteri, four, five, six, seven and eight days after coitus, 2-celled eggs six and seven days after, 4-celled eggs eleven and eighteen days after. In one case the young were bom eight days after the last observed act of coitus, in another sixteen days after, and in yet another twenty days after.



Technique

As fixatives, I have employed for ovaries the fluids of Hermann, Flemming, Ohlmacher, and Zenker; for ova and early blastocysts, Hermann, Flemming, Perenyi, and especially picro-nitro-osmic acid (picro-nitric acid [Mayer] 96 C.C., 1 per cent, osmic acid 2 c.c., glac. acetic acid 2 c.c.) ; for later blastocysts, the last-named fluid especiall}'^ also picro-corrosive-acetic aud corrosive-acetic.


To facilitate the handling of ova and early blastocysts during embedding, I found it convenient to attach each specimen separately to a small square of pig’s foetal membrane by means of a dilute solution of photoxylin (1 to 2 per cent.), Orientation of the specimen was then easily effected during final embedding, under the low power of the microscope. The larger blastocysts were double-embedded in photoxylin and paraffin, the cavity of the blastocyst being tensely filled with the photoxylin solution by means of a hypodermic syringe fitted with a fine needle.


For the staining of sections, Heidenhain's iron-htematoxylin method proved the most satisfactory, and was almost exclusively employed. Entire portions of the blastocyst wall were stained either with Ehrlich's or Delafield's haematoxylin.


I am much indebted to Mr. L. Scbaeffer, of the Anatomical Department of the University of Sydney, and to Mr. F. Pittock, of the Zoological Department, University College, for invaluable assistance in the preparation of the photomicrographs reproduced on Plates 1 - 5, and also to Mr. A. Cronin, of Sydney, and Miss M. Rhodes, for the drawings from their respective pencils reproduced on Plates 6 aud 7. To Miss V. Sheffield I am indebted for tlie original of fig. 63.

To my friend Dr. F. P. Sandes, Sydney, I am indebted for kind help in the revision of certain parts of the manuscript.


Historic Disclaimer - information about historic embryology pages 
Mark Hill.jpg
Pages where the terms "Historic" (textbooks, papers, people, recommendations) appear on this site, and sections within pages where this disclaimer appears, indicate that the content and scientific understanding are specific to the time of publication. This means that while some scientific descriptions are still accurate, the terminology and interpretation of the developmental mechanisms reflect the understanding at the time of original publication and those of the preceding periods, these terms, interpretations and recommendations may not reflect our current scientific understanding.     (More? Embryology History | Historic Embryology Papers)

Contents: 1 Review of Previous Observations | 2 The Ovum of Dasyurus | 3 Cleavage and Blastocyst | 4 Blastocyst Growth Ectoderm Entoderm | 5 Early Stages of Perameles and Macropus | 6 Summary and Conclusions | 7 Early Mammalia Ontogeny | Explanation of Plates


Cite this page: Hill, M.A. (2020, April 10) Embryology Paper - Contributions to the embryology of the marsupialia 4. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Paper_-_Contributions_to_the_embryology_of_the_marsupialia_4

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