THE ANATOMY OF TEN TO TWELVE MM. PIG EMBRYOS 



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the posterior extremities. The reduction in the trunk flexures is due to the in- 

 creased size of the heart, liver, and mesonephroi. These organs may be seen 



Brani'hidl rirfl i 

 II void an k 



Cermcal flexure 

 Branchial arch 3 



Cervical sinus 



Myelencephalon 



Upper limb bud — - 



Milk line 



Mesodermal segment 



\yCephaUc flexure 



f 

 "Eye 



Maxillary process 

 M andihiilar process 

 Olfactory pit 



0^^^Umhili 



cal cord 



« Loiver limb bud 



Fig. 118. — Exterior of a 10 mm. pig embryo viewed from the right side. X 7. 



through the translucent body wall and the position of the septum transversum 

 may be noted between the heart and the diaphragm, as in Fig. 120. The limb 



C e plialic flexure 

 Eye 



Maxillary process 

 -, — ■ Attachment of amnion 



External ear. 



M andibular process. 



Upper limb bud 



Mesodermal segment 



.Lower limb 



Fig. 119. — Exterior of a human embryo of 12 mm., viewed from the right side, showing attachment 

 of amnion (cut away) and yolk stalk and sac. X 4. 



buds are larger and the umbihcal cord is prominent ventrad. Dorsally the meso- 

 dermal segments may be seen, and extending in a curve between the bases of the 



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