File:Keibel Mall 2 587.jpg

Fig. 587. — Portion of a section through the kidney of a human embryo of 30 mm. vertex-breech length. (From the collection of Professor Stoerck, Vienna; II. 1, 7.) X 300. The anlagen of two uriniferous tubules are cut by the section. They are in different stages of development, belong to different generations, and therefore he at different levels. The left upper anlage has developed a uriniferous tubule that has connected with the collecting tubule. It has a club-shaped form, the handle of the club being represented by the uriniferous tubule and its head by the anlage of Bowman's capsule. A slight groove begins to grow in on the left side, marking the limits between the tubule and the capsule. The lower right tubule is just about to form Stoerck's loop. Its parts are not continuous in the section. Below is Bowman's capsule, still shell-shaped; then comes a portion curved like the letter S, and from the upper limb of the S a convoluted tubule arises; the middle limb is the parent tissue for Stoerck's loop and the lower one becomes the connecting piece. Above the S is the intermediate piece cut transversely.