xvi PROTOPLASM 



PLATE 



X. Blood corpuscles of the frog (Fig. 1, a and b) ; axis-cylinder, in trans- 

 verse section, of the rabbit (Fig. 2) ; pseudopodium of Actinosphwrium 

 (Fig. 3) ; structure of a thin lamella of oil-foam (Fig. 4) ; and draw- 

 ings to show the optical network, produced by intersection of dif- 

 fraction rings, between minute suspended droplets of oil (Fig. 5, 

 a-c). 



XI. A thin section through the cuticle and hooks of Distomum. 



XII. Pseudopodium of A ctinosphcerium (Fig. 1); protoplasmic filament from 

 a cell of Tradescantia (Fig. 2) ; section through cells of the intestinal 

 epithelium of Distomum (Fig. 3) ; stalk muscle of Zoothamnium (Fig. 

 4) ; and tentacle of Acineta in optical section (Fig. 5). For Fig. 6 

 compare the text, p. 179. 



