LIST OF ILLUSTRATIONS. xvii 



FIG. PAGE 



198. Section of a Very Young Human Chorion , 343* 



199. Portion of the Preceding Figure More Highly Magnified 344 



2CX5. Aborting Villus from the Human Chorion Lseve of the Second Month, 346 



201. Fragment of the Chorion of Fig. 69, Highly Magnified, ■- 346 



202. Isolated Terminal Branch of a Villus from a Human Chorion of Twelve Weeks, 347 



203. Villous Stem from a Human Placenta of the Fifth Month, 347 



204. Terminal Branches of a Villus from a Human Placenta at Full Term, 347 



205. Portion of an Injected Villus from a Placenta of about Five Months, 347 



206. Portion of a Small Injected Villous Stem from a Placenta of about Five Months, 348 



207. Transverse Section of a Human Amnion of Two Months, 349 



208. Two Sections of the Human Amnion, 350 



209. Surface View of the Human Amniotic Epithelium of the Fourth Month, 350 



210. Natural Group of Nuclei from the Mesoderm of the Human Amnion of the Fifth Month, .... 351 



211. Cross-section of a Human Umbilical Cord at Term, . . 352 



212. Section of the Allantois from a Human Umbilical Cord of Three Months, 352 



213. Connective Tissue from the Umbilical Cord of a Human Embryo of 21 mm. Stained with Alum 



Cochineal and Eosin, 352 



214. Connective Tissue from the Umbilical Cord of a Human Embryo of Three Months, Stained with 



Alum Cochineal and Eosin, 353 



215. Ectoderm of an Umbilical Cord of a Human Embryo of Three Months, 354 



216. Section of the Yolk-sac of a Very Young Human Embryo {after Fr. Keibel") 355 



217. The Precision Microtome, "... 361 



218. The Automatic Rotary Microtome, 362 



