INDEX 



245 



Michaiix, 180. 



Midwife toad, 232. 



Milk glands, 96. 



Mole, eyes of, 189. 



Monotremata, origin of milk glands, 

 136. 



Morgan, T. H., 21, 233; on blind- 

 ness in cave animals, 189 ; on 

 mutations, 174, 175 ; on sex, CO ; 

 on sex-linked heredity, 112; on 

 sexual dimorphism in Drotophila, 

 120 ; on variation, 201. 



Mutations, 174 ; in antlers, 128. 



Natural selection, 6, 15, 37. 

 Nuptial plumage, 83. 

 Nussbaum, 163. 

 Nyssia zonaria, 161. 



O'DoNOGHUE, 98, 101 ; development 



of milk glands, 135. 

 (Enothera, mutations, 180 ; grandi- 



flora, 180; lata, 178, 181; La- 



marckiana, 178-181. 

 Onagra, species of, 180. 

 Origin of Species, Darwin's, 6. 

 Ornithorhynchus, corpus luteum, 142. 

 Orthogenesis, 181. 

 Otariidae, scrotum, 151. 

 Ovaries, position of, 151. 

 Ovary, in birds, 1 83. 

 Ovulation, 145. 



Pangenesis, 241. 



Parthenogenesis, 56. 



Parturition, 146. 



Pearson, Karl, 40. 



Pheasant, male, 83 ; gjmandromor- 



phism in, 155. 

 Phillips, JohnC, 185. 

 Philosophie Zoologigue, 11. 

 Phocidae, testes, 151. 

 Physiology of Reproduction, 142. 

 Picotee Sweet Pea, 50, 173. 

 Pigeons, 46. 

 Pigment, absence in cave animals, 



191. 

 Pile fowls, 47. 

 Pintail duck, crosses, 186. 

 Plaice, 25. 

 Pleuronectes jiesuf>, 25 ; glacialis, 27 ; 



platessa, 25. 

 Plymouth Rock fowl, 115. 

 Pole-dab, 20. 

 Poll, 156. 



Preformation, 174. 

 Problems of Genetics, 17. 

 Prong-buck, 165. 



Pro-oestrus, 146. 



Protcu$, 185 ; eyes of, 189, 



Prototheria, milk glands in, 136. 



Rabbits, lactation in, 97. 

 Recapitulation, absence of, 225 ; and 



mutations, 203. 

 Reptiles, corpora lutea in, 143. 

 Reversal, in Flat-fishes, 206. 

 lihinoderma darivinii, 70. 

 Ribbert, 97. 

 Rieger, 76. 

 Rodents, testes, 152. 

 Romanes, 17. 



Rontgen rays, effect on testes, 95. 

 Rose comb, in fowls, 43. 

 Rotifers, heredity of sex in, 56. 

 Ruhricalyx, (Enothera, 182. 

 Ruhrinervis, (Enothera, 182. 



Sacculina, 166. 



Salamanders, transplantation of eye, 



190. 

 Sandes, 144. 

 Schuster, Edgar, 163. 

 Scrotum, origin of, 147. 

 Sea-horse, 28. 



Secondary sexual characters, 67. 

 Selheim, 76. 



Semilata, (Enothera, 183. 

 Sertoli's cells, 93. 

 Sex, 37; chromosomes, 59; Mendelian 



theory of, 53. 

 Sex-linked heredity, 108. 

 Sexual Dimorphism, 68. 

 Sexual dimorphism, 119 ; in Rajidae, 



222; in Plaice, 220, 221. 

 Shattock and Seligmann, 75, 156. 

 Silkworm, 158. 



Silky fowl, 44, 46 ; plumage of, 178. 

 Sirenia, absence of scrotum, 150. 

 Slow-worm, 227. 

 Smith, Geoffrey, 163, 166-168. 

 Snakes, absence of limbs, 226. 

 Sociology, 242. 



Somatic sexual characters, 67, 68. 

 Species, conception of, 9 ; origin of, 



11, 14, 21 ; characters of, 37 ; 



sterility and hj'bridism, 1S5. 

 Spermatogenesis, in man, 115. 

 Starling and Lane-Claypon, on lacta- 

 tion, 97. 

 Steinach, 104 ; heredity of milk 



glands, 136. 

 Sternum, carina of, 229. 

 Swallows. 36. 

 Sweet Pea, 187- 

 Swifts, 36. 



