Figure 7. Table II illustration from Wolff's "On the Formation 

 of the Intestine . " 



1. Embryo of 4 days incubation; r — excised part of the vascular 

 area on which the vesicle lies; a, b, c — vesicle or false 

 amnion; g, h, i, 1— — translucent embryo; h— — occiput; 



g — anterior part of the head; i — vertebra; 1 — left wing; 

 k — left auricle; B — left lateral part of thorax; 

 C — fold of abdominal opening and true amnion (Table I , 

 Fig. 2, ii, Fig. 7, xx) ; e — intestinal fold and fold of 

 false amnion (see Table I, Fig. 7, n) ; m — opening between 

 true and false amnion; d — part of middle intestine; f — 

 rounded fossa, appearing from cardiac fossa, groove and 

 lower fossa; N — lower fossa; p — right yolk vein; o — artery 

 of that side; n — left yolk artery; q— -umbilical vesicle 

 (allantois) . 



2. The same object with extracted false amnion; a — part of 

 upper layer of vascular area; b— -true amnion; c — occiput; 

 d — anterior part of the head; D— middle protuberance, 

 disappearing after six days; e— -vertebra; f — left wing; 



F — left leg; g — left auricle; h- — lateral part of thorax; 

 i — folds of abdominal opening from which membrane of true 

 amnion takes origin; H, H— -the area of the abdomen, 

 adjacent to the thighs, forming paired cavities in the 

 sides of the vertebrae; E- — backwards-bending part of this 

 cavity; k, 1, m, n, o, p— parts beginning from abdominal 

 cavity; k — intestinal fold from which the membrane of the 

 false amnion continues (n) ; 1 — deeper fold of intestine; 

 m — parts of folded middle intestine; n — part of false amnion; 

 o — its part continuing through the cardiac fossa to the 

 stomach; p— upper part of the rectum. 



3. The same object; amnion destroyed, lateral parts of thorax 

 removed; and also abdominal cavity, extremities and head; 

 viscera is visible; a — left chamber of heart; b — aural canal; 

 c — left auricle; d — arch of aorta; v—— venous sinus; 



f — left lobe of liver; g — rudiment of abdomen; h — digestive 

 tract; i — stomach; k — intestinal fold; 1 — duodenum; MM — 

 middle intestine; n — part of membrane of false amnion; 

 o — part of this membrane covering the intestinal canal; 

 p— upper funnel-shaped part of the rectum; q — lower part 

 of rectum, which, like the stomach, also already has 



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