File:Pohlman1911 plate1.jpg - Revision history

Z8600021 at 23:57, 26 September 2018

2018-09-26T23:57:09Z

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	==Plate 1==		==Plate 1==

	[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall ~~[[:Category:Carnegie Embryo 164\|164]]~~; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane - the tail gut - is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)		[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall {{CE164}}; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane - the tail gut - is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)


	[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] Embryo No. 5 (Mall ~~[[:Category:Carnegie Embryo 186\|186]]~~; 3.5 mm.; +; 20; Good). x 100. Allantois wide lumened and no distinct line of demarkation from the ventral cloacal segment. Wolflian ducts have arrived but not as yet opened. Tail gut maximum of development. Probably the first signs of cloacal division. [[Carnegie stage 13]]		[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] Embryo No. 5 (Mall no. {{CE186}}; 3.5 mm; +; 20; Good). x 100. Allantois wide lumened and no distinct line of demarkation from the ventral cloacal segment. Wolflian ducts have arrived but not as yet opened. Tail gut maximum of development. Probably the first signs of cloacal division. [[Carnegie stage 13]]

	[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] {No. 5; Mall no. ~~186~~; 3.5 mm.) This model, although made from an embryo of the same length as the above, shows a distinctly older stage in the development of the tract. The allantois has a much wider lumen and the angle between it and the hind gut is much more acute. The Wolffian ducts have reached the cloaca, and attach but do not open into it ventrally near the upper limit of the cloacal membrane. The tail gut is much larger both in length and in thickness, and terminates in an undifferentiated cell mass formed by itself, the chorda and the neural tube (shown as a knob-like ending). The cloaca is wider dorsally than ventrally. A stage similar to the one described was found in two other embryos (nos. 7 and 8), in both of which the allantois was wide at its apparent opening into the cloaca. The possibility of some minor degree of development abnormality suggested itself but on careful study, it was decided that the first evidences of cloacal division were at hand.		[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] {No. 5; Mall no. {{CE186}}; 3.5 mm) This model, although made from an embryo of the same length as the above, shows a distinctly older stage in the development of the tract. The allantois has a much wider lumen and the angle between it and the hind gut is much more acute. The Wolffian ducts have reached the cloaca, and attach but do not open into it ventrally near the upper limit of the cloacal membrane. The tail gut is much larger both in length and in thickness, and terminates in an undifferentiated cell mass formed by itself, the chorda and the neural tube (shown as a knob-like ending). The cloaca is wider dorsally than ventrally. A stage similar to the one described was found in two other embryos (nos. 7 and 8), in both of which the allantois was wide at its apparent opening into the cloaca. The possibility of some minor degree of development abnormality suggested itself but on careful study, it was decided that the first evidences of cloacal division were at hand.


	[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']], other than a better developed tail gut, a slightly higher position of the Wolffian ducts and a shorter cloacal membrane agrees with Keibel's model of the 4.2 mm. embryo. Keibel's model shows this same evidence of division; a frontal septum between the allantois and hind gut slipping down to a level approaching the upper limit of the cloacal membrane. The writer has found no embryo where the cloacal membrane approaches the level of the dermal navel, and will consider this point later.		[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']], other than a better developed tail gut, a slightly higher position of the Wolffian ducts and a shorter cloacal membrane agrees with Keibel's model of the 4.2 mm embryo. Keibel's model shows this same evidence of division; a frontal septum between the allantois and hind gut slipping down to a level approaching the upper limit of the cloacal membrane. The writer has found no embryo where the cloacal membrane approaches the level of the dermal navel, and will consider this point later.

Z8600021 at 04:30, 15 Haziran 2016

2016-06-15T04:30:40Z

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	[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane - the tail gut - is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)		[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane - the tail gut - is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)


			[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] Embryo No. 5 (Mall [[:Category:Carnegie Embryo 186\|186]]; 3.5 mm.; +; 20; Good). x 100. Allantois wide lumened and no distinct line of demarkation from the ventral cloacal segment. Wolflian ducts have arrived but not as yet opened. Tail gut maximum of development. Probably the first signs of cloacal division. [[Carnegie stage 13]]

			[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] {No. 5; Mall no. 186; 3.5 mm.) This model, although made from an embryo of the same length as the above, shows a distinctly older stage in the development of the tract. The allantois has a much wider lumen and the angle between it and the hind gut is much more acute. The Wolffian ducts have reached the cloaca, and attach but do not open into it ventrally near the upper limit of the cloacal membrane. The tail gut is much larger both in length and in thickness, and terminates in an undifferentiated cell mass formed by itself, the chorda and the neural tube (shown as a knob-like ending). The cloaca is wider dorsally than ventrally. A stage similar to the one described was found in two other embryos (nos. 7 and 8), in both of which the allantois was wide at its apparent opening into the cloaca. The possibility of some minor degree of development abnormality suggested itself but on careful study, it was decided that the first evidences of cloacal division were at hand.


			[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']], other than a better developed tail gut, a slightly higher position of the Wolffian ducts and a shorter cloacal membrane agrees with Keibel's model of the 4.2 mm. embryo. Keibel's model shows this same evidence of division; a frontal septum between the allantois and hind gut slipping down to a level approaching the upper limit of the cloacal membrane. The writer has found no embryo where the cloacal membrane approaches the level of the dermal navel, and will consider this point later.


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	{{Pohlman1911 figures}}		{{Pohlman1911 figures}}
	[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]		[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]
			[[Category:Carnegie Embryo 186]][[Category:Carnegie Stage 13]]

Z8600021 at 04:20, 15 Haziran 2016

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	==Plate 1==		==Plate 1==

	[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane ~~â€”~~ the tail gut ~~â€”~~ is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)		[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane - the tail gut - is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)

Z8600021 at 04:19, 15 Haziran 2016

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	==Plate 1==		==Plate 1==

	[[:File:Pohlman1911 plate1A.jpg\|Model A]] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]]		[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane â€” the tail gut â€” is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)



	{{Pohlman1911 figures}}		{{Pohlman1911 figures}}
	[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]		[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]

Z8600021 at 04:17, 15 Haziran 2016

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← Older revision		Revision as of 15:17, 15 Haziran 2016
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	==Plate 1==		==Plate 1==

	[[:File:Pohlman1911 plate1A.jpg\|Model A]] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]]		[[:File:Pohlman1911 plate1A.jpg\|Model A]] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]]


	{{Pohlman1911 figures}}		{{Pohlman1911 figures}}
	[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]		[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]

Z8600021 at 04:17, 15 Haziran 2016

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	==Plate 1==		==Plate 1==

			[[:File:Pohlman1911 plate1A.jpg\|Model A]] Embryo No. 3 (Mall [[:Category:Carnegie Embryo 164\|164]]; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]]


	{{Pohlman1911 figures}}		{{Pohlman1911 figures}}
	[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]		[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]

Z8600021 at 04:16, 15 Haziran 2016

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	==Plate 1==		==Plate 1==


	{{Pohlman1911 figures}}		{{Pohlman1911 figures}}
			[[Category:Carnegie Embryo 164]][[Category:Carnegie Stage 11]]

Z8600021 at 03:32, 12 Haziran 2016

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	{{Pohlman1911 figures}}		{{Pohlman1911 figures}}

	~~===Reference===~~
	~~{{Ref-Pohlman1911}}~~

	~~{{Footer}}~~

Z8600021 at 01:54, 11 Haziran 2016

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			==Plate 1==

			{{Pohlman1911 figures}}

	===Reference===		===Reference===
	~~Pohlman AG. The development of the cloaca in human embryos. (1911) Amer. J Anat. 12.~~		{{Ref-Pohlman1911}}

			{{Footer}}

Z8600021: ===Reference=== Pohlman AG. The development of the cloaca in human embryos. (1911) Amer. J Anat. 12.

2016-06-11T01:45:59Z

===Reference=== Pohlman AG. The development of the cloaca in human embryos. (1911) Amer. J Anat. 12.

New page

===Reference===
Pohlman AG. The development of the cloaca in human embryos. (1911) Amer. J Anat. 12.

← Older revision		Revision as of 10:57, 27 September 2018
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	==Plate 1==		==Plate 1==

	[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall ~~[[:Category:Carnegie Embryo 164\|164]]~~; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane - the tail gut - is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)		[[:File:Pohlman1911 plate1A.jpg\|'''Model A''']] Embryo No. 3 (Mall {{CE164}}; 3.5 mm. ; + ; 20; Good). x 100. Cloaca well developed and limited for caudal half of the ventral border by epithelial cloacal membrane. Allantois comes off at right angles and at lower border of dermal navel. Lateral furrow along later line of division. [[Carnegie stage 11]] This model shows the cloaca to be a sort of conical sac receiving the wider lumened hind gut dorsally, and the narrow lumened allantois ventrally. The latter joining the cloaca at about a right angle. The cloaca is much wider dorsally and is somewhat wedged-shaped in section. Ventrally, it is limited for about one-half of its extent by the epithelial cloacal membrane which is indicated by a surface contact. The right wall of the cloaca is concaved from before backwards while the left side (shown) is correspondingly convex, and presents a well marked furrow extending from the saddle between the allantois and hind gut to about the mid area of the cloacal membrane. This furrow is interesting because while it indicates the probable line of the later division, it was found in but two embryos of the series examined. The part of the cloaca caudal to the cloacal membrane - the tail gut - is quite short and cone-shaped. The model with the exception of the furrow conforms to Keibel's model of the His embryo EB (3 mm.)


	[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] Embryo No. 5 (Mall ~~[[:Category:Carnegie Embryo 186\|186]]~~; 3.5 mm.; +; 20; Good). x 100. Allantois wide lumened and no distinct line of demarkation from the ventral cloacal segment. Wolflian ducts have arrived but not as yet opened. Tail gut maximum of development. Probably the first signs of cloacal division. [[Carnegie stage 13]]		[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] Embryo No. 5 (Mall no. {{CE186}}; 3.5 mm; +; 20; Good). x 100. Allantois wide lumened and no distinct line of demarkation from the ventral cloacal segment. Wolflian ducts have arrived but not as yet opened. Tail gut maximum of development. Probably the first signs of cloacal division. [[Carnegie stage 13]]

	[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] {No. 5; Mall no. ~~186~~; 3.5 mm.) This model, although made from an embryo of the same length as the above, shows a distinctly older stage in the development of the tract. The allantois has a much wider lumen and the angle between it and the hind gut is much more acute. The Wolffian ducts have reached the cloaca, and attach but do not open into it ventrally near the upper limit of the cloacal membrane. The tail gut is much larger both in length and in thickness, and terminates in an undifferentiated cell mass formed by itself, the chorda and the neural tube (shown as a knob-like ending). The cloaca is wider dorsally than ventrally. A stage similar to the one described was found in two other embryos (nos. 7 and 8), in both of which the allantois was wide at its apparent opening into the cloaca. The possibility of some minor degree of development abnormality suggested itself but on careful study, it was decided that the first evidences of cloacal division were at hand.		[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']] {No. 5; Mall no. {{CE186}}; 3.5 mm) This model, although made from an embryo of the same length as the above, shows a distinctly older stage in the development of the tract. The allantois has a much wider lumen and the angle between it and the hind gut is much more acute. The Wolffian ducts have reached the cloaca, and attach but do not open into it ventrally near the upper limit of the cloacal membrane. The tail gut is much larger both in length and in thickness, and terminates in an undifferentiated cell mass formed by itself, the chorda and the neural tube (shown as a knob-like ending). The cloaca is wider dorsally than ventrally. A stage similar to the one described was found in two other embryos (nos. 7 and 8), in both of which the allantois was wide at its apparent opening into the cloaca. The possibility of some minor degree of development abnormality suggested itself but on careful study, it was decided that the first evidences of cloacal division were at hand.


	[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']], other than a better developed tail gut, a slightly higher position of the Wolffian ducts and a shorter cloacal membrane agrees with Keibel's model of the 4.2 mm. embryo. Keibel's model shows this same evidence of division; a frontal septum between the allantois and hind gut slipping down to a level approaching the upper limit of the cloacal membrane. The writer has found no embryo where the cloacal membrane approaches the level of the dermal navel, and will consider this point later.		[[:File:Pohlman1911 plate1B.jpg\|'''Model B''']], other than a better developed tail gut, a slightly higher position of the Wolffian ducts and a shorter cloacal membrane agrees with Keibel's model of the 4.2 mm embryo. Keibel's model shows this same evidence of division; a frontal septum between the allantois and hind gut slipping down to a level approaching the upper limit of the cloacal membrane. The writer has found no embryo where the cloacal membrane approaches the level of the dermal navel, and will consider this point later.