FIG. 
LIST OF ILLUSTRATIONS. 
1. Pineal eye of lizard (Hatteria) (after Spencer) . 
wi nN 
. Pineal eye of lizard, in section (after Spencer) ‘ 
. Head of horned toad (Phrynosoma) (after nature, by 
W.S. Atkinson) . 
. Conjugation of Infusoria (after Leueleaty) 
. Karyokinesis of cell (after Driiner) . 
. Reduction of chromatin in egg-cleavage (ater Boveri) . 
. Development of Pandorina (after Pringsheim) 
. Colony of Eudorina with antherozooids (after Goebel) 
. Diagram of development of spermatozoa (after Boveri) . 
. Fertilization of egg (after Boveri) 
. Reduction of chromosomes in developing egg ter 
Brauer). o 
. Maturation of egg of ‘Bees (after Riickert) 
. Larva of Echinus (after Boveri) 
. Hybrid larva of Echinus and Spherechinus (after Bieri 
. The arctic birch (after nature, by Anne L. Brown). 
. Skeleton of greenling (Hexagrammos) (after nature, by 
W.S. Atkinson) 
. Skeleton of scarlet rock-fish (Sebastodes) atte nature, by 
W. S. Atkinson) . 
. Skeleton of angel fish (Angetichebys) (after 2 nature, by 
W. S. Atkinson) 
. Sacculina after leaving the egg (after Lang) 
. Sacculina attaching itself (after Lang) 
. Sacculina, an early stage (after Lang) ‘ 
. Sacculina after absorption of limbs (after Lang) 
. Adult Sacculina attached to crab (after Lang). 
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