XVI 



LIST OF ILLUSTRATIONS 



FIGURE 



85. Diagram of the conjugation of an Infusorian 



86. Conjugation of an Infusorian ..... 



87. Diagram to illustrate the operation of amphimixis 



88. Sperm-mother-cells (spermatocytes) of the Salamander 



89. Anterior region of the larva of a Midge 



90. The Common Shore-Crab, seen from below . 



91. Hind leg of a Locustid . .... 



92. Echinoderm-larva? ..... 



93. Development of a limb in the pupa of a Fly 



94. Diagram to illustrate the phylogenetic shifting back of the origins 



of the germ-cells in medusoids and hydroids . 



95. Diagram to illustrate the migration of the germ-cells in Hydromedusse 



364 



PAGE 



321 

 323 



348 

 350 

 393 

 367 

 371 

 387 

 395 



412 

 414 



( OLOXTRED PLATES 



SOME MTMET1C BUTTERFLIES AND THEIR IMMUNE MODELS 



Plate I . 

 Plate II . 

 Plate III 



to face page 112 



„ „ 114 

 „ „ 116 



