LIST OF ILLUSTRATIONS. xxi 



JIG. PAGE 



203. Outline figure of a human embryo lettered by Professor His, A, and 



estimated as twenty-seven days old. (From His) . . . 493 



204. Human embryo lettered by Professor His, A, and estimated as 



twenty-seven days old. (After His) 494 



205. Outline figure of a human embryo lettered by Professor His, Rg, and 



estimated as thirty-two or thirty-three days old. (From His) . 497 



206. The under surface of the head of a human embryo lettered by Pro- 



fessor His, Hn, and estimated as about twenty-nine days old. 

 (After His) 498 



207. The under surface of the head of a human embryo lettered by Pro- 



fessor His, C.IL, and estimated as about thirty-four days old. 

 (After His) 498 



208. The left ear of a human embryo lettered by Professor His, Br. 2, and 



estimated as thirty-five days old. (From His) .... 500 



209. The left ear of a human embryo lettered by Professor His, Dr, and 



estimated as thirty-eight days old. (From His) .... 600 



210. A pregnant uterus of about the fortieth day. (From Kolliker, after 



Coste) 501 



211. Outline figure of -a human embryo about the middle of the sixth 



week. (From His) . 503 



212. Outline figure of a human embryo at the end of the second month. 



(From His) . . - . .504 



213. Head of a human embryo at the end of the seventh week. (After 



His) 505 



214. Head of a human embryo at the end of the second month. (After 



His) . . . . 505 



215. The head and fore part of the body of a human embryo lettered by 



Professor His, Lr, and estimated as twenty or twenty-one days 

 old. (After His) 511 



216. Human embryo lettered by Professor His, Pr, and estimated as 



twenty-eight days- old. The brain is exposed from the left 

 side, and the body of the embryo has been dissected to show the 

 heart and aortic arches and the alimentary canal. (After His) 512 



217. The brain of a human embryo lettered by Professor His, ZW, and 



estimated as about the middle of the eighth week. (After His) 513 



218. A human fcetus three months old, dissected from the dorsal surface 



to expose the brain and spinal cord. (From Kolliker) . . 514 



219. The brain of a human foetus three months old, from the right side. 



(From Kolliker) 515 



220. The brain of a human foetus three months old, dissected from the 



dorsal surface. (From Kolliker) 515 



221. The brain of a human foetus three months old, from the ventral 



surface. (From Kolliker) . . 515 



222. The brain and spinal cord of a human foetus four months old, from 



the dorsal surface. (From Kolliker) 515 



223. The brain of a human fcetus six months old, from the right side. 



(From Kolliker) 515 



224. The brain of a human fcetus of the fifth month, bisected, and seen 



from the inner surface. (From Kolliker) 518 



225. A transverse section through a portion of the wall of the spinal 



