272 



INDEX 



Retina, development of, 140 



pars ciliaris of, 140 



rods and cones of, 140 



hexagonal pigment-epithelium of, 140 



nerve-fibre layer of, 140 



central artery of, 142, 221 

 Retterer, on development of cloaca! region, 203 

 Retzius, on zona radiata, 8 



epithelial plug in nostril, 88 

 Reuter, on eye-muscles, 248 



masticatory muscles in pig, 248 

 Rhinencephalon, 116,122 

 Rhinopallium, 122 



Rhombencephalon, or hind-brain, 106 

 Rhombic brain, appearance of segmentation 

 in, 129 



lips, formation of, 108 

 Ribs, development of, 252 

 Ridge, Wolffian, appearance of, 84, 178 



relation of pleuro-peritoneal mem- 

 branes to, 241 



genital, 186 

 Robinson, on secondary caudal arch, 223 



pericardial coelom, 237 

 Rodents, allantois in, 55 

 Rods of Corti, 148 

 Rolando, origin of substance of, 108 

 Riickert, on ventral mesoderm, 34 



theory of origin of blood-vessels, 62 



theory of origin of Wolffian duct, 178 

 Ruge, on development of sternum, 253 



SABIN, on origin of lymphatics, 236 

 Sac of peritoneum, lesser, 244 

 Salzer, on primitive jugular vein, 231 

 Sauropsida, vascular area in, 59 

 Schonemann, on nasal fossa, 155 

 Schreiner, on nephrogenetic cord, 182 

 Schultze, 0., theory of origin of nerves, 100 



on cartilaginous stage of vertebral column, 

 251 



division of sclerotomes in mammalia, 250 

 Schwann, origin of sheath of, 99, 100 

 Scleromeres or primitive vertebrae (Bardeen), 



250 



Sclerotic, 143 

 Sclerotomes, 56, 250 

 Scrotum, 199, 203 

 Secreting tubules, origin of, 184 

 Sedgwick, on phylogeny of primitive streak, 48 



theory of primitive nerves, 100 

 Seessel's pocket, 157 

 Segmentation nucleus, 15 



without fertilisation, 17 



of ovum, 25 



place of occurrence of, 86 



mesodermic, 50 



of the head, question of, 249 

 Segments, mesodermic or primitive, 49, 50 



order of appearance of, 50 



development of cavity in, 51 



preoccipital, cleavage of, in lower verte- 

 brates, 57 



of limbs, appearance of, 89 

 Selachians, relation of mesodermic segmenta- 

 tion to notochord in, 50 



sympathetic ganglion cells in, Balfour, 135 



branchial sense organs in, 128 



fate of cellular elements in spleen, 237 



liver-parenchyma in, 174 



Selachians, development "of eye-muscles in, 248 



head-segmentation in, 249 

 Selenka, on entypy of germinal area, 31 



early mesoderm in Semnopithecus, 34, 35 



ovum of Macacus nemestrinus, 25 



Hylobates embryos, 30 



blastoporic aperture in opossum, 43 



early blood-vessels in chorion in Hylobates 



rafflesi, 60 

 Seminal tubules, 191 



vesicle, 192 

 Semnopithecus nasicus, early mesoderm in, 



34,35 

 Sensory nerve roots, origin of, 98 



roots of cerebral nerves, 128 

 Septum, aortic, 216, 218 



lucidum, 122, 124 



spurium, 212 



inferius, His, 212 



primum, Born, 212 



secundum, Born, 212 



transversum, 54, 238 



sinus venosus in, 206 

 Sertoli, cells of, in spermatogenesis, 6 

 Sex, Minot's theory of, 20 



establishment of characters of, 90 



in genital glands, 189 

 Sexual cells, history of, 5 et seq. 



dimorphism of, 13 



development of primitive, 188 

 Shield, embryonic, 37 

 Shrew, origin of middle layer in, Hubrecht, 36 



blastoporic aperture in, Hubrecht, 43 

 Simon, on lateral lobe of thyroid, 169 

 Sinus ensiformis, Eternod, 60 



precervical, 84, 88 



urogenital, 164, 185 



cavernous, 229 



lateral, 229 



superior petrosal, 229 



inferior petrosal, 229 



venosus, 206 



Sinusoids, Minot, 174, 224 

 Skeleton, development of, 250 

 Skin, development of, 93 



stratum corneum of, 94 

 Skull, development of, 254 

 Sobotta, on fertilisation in mouse, 14 

 Soma, 1 



history of, 25 

 Somatopleure, in lower mammals, 33 



in higher mammals, 51 



giving rise to amnion-folds, 34 

 Soulie, on origin of adrenals, 206 

 Spee, on early mesoderm in human ovum, 35 



changes in wall of yolk-sac, 60 



age of ova described by, 80 



imbedding of ovum in guinea-pig, 67 



origin of Wolffian duct from ectoderm, 178 

 Sperm -aster, 15 

 Spermatic fascia, 199 

 Spermatids, 6 

 Spermatocyte, 6 

 Spermatogonium, 6, 192 

 Spermatozoon, structure of, 5 



accession of, to ovum, 9 



fertilisation by, 14 



changes in, corresponding to maturation, 



18 

 Sperm-nucleus, 15 







