THE BEAIN, 



373 



Fig. 150. — A mediae longitudinal, or sagittal section through a Eabbit Embryo 

 at tlie end of the twelfth day. The section is a strictly median one except 

 in two respects : the cerebral hemisphere of the left side has been intro- 

 duced in order to render the figure more complete; and theWolflSan body 

 and ureter of the right side. The terminal portion of the tail has been 

 removed. (Compare Fig. 161 for a, surface view of an embryo of the 

 same age.) x 14. 



BF, cavity of fore-brain or tlaalamenceplialon. BH, cavity of liind-braiii, or fourth 

 ventricle. BL, cerebellum. BM, cavity of mid-brain. BS, cavity of cerebral hemi- 

 sphere, or lateral ventricle. CH, notochord. GP, post-aual gut. IN, finger-like 

 process of infundibulum. KC, Wolffian duct. KD, ureter. KM, Wolffian body. 

 IiE, epiglottis. LGr, lung. LK, trachea. PIT, pineal body. PT, pituitary body. 

 RS, sinus venosus. E.T, truucus arteriosus. RV, ventricle of heart. T, glottis. 

 TA, stalk of allantois, cut short. TC, cloaca. TH, thyroid body. TO, oesophagus. 

 TP, pharynx. "W, liver. "WD, bile duct. YK, yolk-stalk, cut short. 



