xiv ILLUSTRATIONS 



I'AOK 



45. Section through follicle in late stage - - 1 .12 



46. Section through human testis and epididymis . 160 



47. Section through testis of monkey - - 161 



48. Section through portion of two seminiferous tubules in testis of rat - li-J 



49. A cell of Sertoli with which the spermatids are beginning to be connected 



(human) - 163 



50. Diagram illustrating the cycle of phases in spermatogeni-q^ - hU 



51. Scheme of spermatogenesis and oogenesis - - 165 



52. Human spermatozoa on the flat and in profile 167 



53. Human spermatozoa - - 168 



54. Different forms of spermatozoa from different species of animals - 169 



55. Diagram illustrating wave-like movement of swimming spermatozoon 171 



56. Successive stages in the fertilisation of an ovum of />/"'- ,.<///,</"*, 



showing the entrance of the spermatozoon - 1 s 1 



57. Three stages in the conjugation of male and female nucleus (AVA /'//)(*) - is2 



58. Fertilisation process in bat's ovum 1 S3 



59. Chart showing amounts of oxygen taken up and carbon dioxide given off 



after the addition of sperm to the eggs of Ei-h/mi* J92 



60. The insemination of the eggs of Saccocirt-tt* - 193 



61. The entrance of the spermatozoon into the egg of X> ret* - 19.1 



62. Passage of convoluted seminiferous tubules into straight tubules, etc. 240 



63. Transverse section through the tube of the epididymis - 2 J I 



64. Transverse section through commencement of vas deferens 242 



65. Section through part of human prostate 247 



66. Section through prostate gland of monkey - 249 



67. Transverse section through adult human penis - - 2.1.1 



68. Section through erectile tissue - 256 



69. Part of transverse section through penis of monkey - 257 



70. Distal end of ram's penis, showing glans and h'liform appendage - 259 



71. Transverse section through filiform appendage of ram 2.19 



72. Transverse section through middle of glans penis of ram - - 260 



73. Distal end of bull's penis, showing glans, etc. - 261 



74. Knd-bulb in prostate - -JO'.) 



75. Diagram illustrating innervation of .genital organs of male cat '_'7I 



76. Herdwick ram (normal) 323 



77. Herdwick wether (castrated young) - - 323 

 7M. Herdwick wether castrated when four months old - 324 

 79. Herdwick wether castrated when five months old - 324 

 MI. Herdwick ram lamb with one testis removed - 324 

 81. Herdwick wether with epididymes retained - 324 

 s2. Successive stages in the regression of the comb of the cock after castration 335 

 S3. Ovariotomised brown Leghorn hen - :!4'_' 

 84. Ovariotomised pullet with plumage and spurs of male - 3J-J 

 s.">. Successive stages in the growth of the spurs of a hen after ovariotomy 343 



86. Normal Rouen drake - 344 



87. Normal Rouen duck 34.1 



88. Ovariotomised Rouen duck (Type I.) 34.1 



89. Ovariotomised Rouen duck (Type II.) 346 



90. Transverse section through rabbit's uterus after ovariotomy 349 



91. Transverse section through bitch's uterus 9J months after ovariotomy -'U'.i 



92. Section through ovary of rat after transplantation on to peritoneum - 3.11 



93. Section through ovary of rat after transplantation on to peritoneum 



94. Transverse section through normal uterus of rat 353 



95. Transverse section through uterus of rat after ovariotomy - - 354 

 9U. Transverse section through uterus of rat after ovarian transplantation 355 

 96A. Section through rat's kidney into the tissue of which an ovary had been 



transplanted - - 3.17 



