LIST OF FIGURES xi 



I'ACE 



Protective Resemblance of Leaf Butterfly, Kallima 1065 

 Structure of Typical Hydrozoon Polyp 1066 

 Two Deep-sea Pennatulids, Funiculina and Chunella 1067 

 Adaptation of Floating Barnacle 1069 

 One of the Sea-pens or Pennatulids 1072 

 Saw of Sawfish, Pristis 1075 

 Deep-sea Fish, Gastrostomus. After Murray 1076 

 Tiger's Skull 1084 

 Skull of Babirussa 1090 

 Hand of the Mole mo 

 Ancestry of Monkeys, Apes, and Man. After Sir Arthur 

 Keith 1 151 

 Fig. 195 . Reconstructions of Heads of Pithecanthropus and of Neander- 

 thal Man. After MacGregor 1152 

 Diagram illustrating the Cell-cycle 1230 

 Diagram illustrating the Field of the Sciences 1240 

 The Biological Prism 1244 

 Parallelism of Biology and Sociology 1253 

 Diagram illustrating Organism and Environment 1254 

 Diagram of Action and Reaction between Organism and 



Environment 1256 



Mendelian Inheritance in Wood Snails. After Lang ^447 



