546 



BASIC FEATURES OF VERTEBRATE MORPHOGENESIS 



GENICULATE GANGLION OF 

 ACOUSTIC GANGLION OF 



AUDITORY VES 



SEVENTH NERVE 



JUGULAR GANGLION OF TENTH NERVE 



ACCESSORY GANGLION 

 BASIL A R ARTER 

 DORSAL ROOT 



GANGLION or FIRST 



CERVICAL NERVE 

 AORTA 

 AORTAL 

 AORTAL 

 AORTAL 

 AORTAL / 

 PULMONAR^ 

 TRAC 

 NOTOCH 

 RIGHT AT 

 LUNG 

 RIGHT VENTR 



GALL 



BLADDER 

 VENTRAL 

 PANCREAS 



DORSAL AO 



OMPHALOMES 

 ARTER 

 (FUTURE SU 

 MESENTERIC 



Fig. 261. Drawings of pig embryos of about 9.5 to 12 mm. (A) Reconstruction of about 

 9.5 to 10 mm. pig embryo with special emphasis on the arterial system. 



derm appear to be the main organizing influence throughout the series (Chap. 

 10), the conclusion is inescapable that the; tubulated embryos of all vertebrates 

 are homologous basically, having the sarrte relative parts, arising in the same 

 manner, and possessing the same basic potencies within the parts. To this 

 conclusion must be added a caution, namely, that, although the main segments 

 or specific organ regions along each body tube of one species are homologous 

 with similar segments along corresponding tubes of other species, variations 

 may exist and non-homologous areas may be insinuated or homologous areas 



