Evolution of Animals 



409 



molluscs, of which examples from the first and last seem clearly 

 to have been of fresh-water origin, is an added argument for 

 the primitive development of all such groups in fresh water, 

 though possibly often in fresh w^ater of a kind that may have 

 been highly charged with dissolved salts. 



In view then of the statistical, phylogenetic, structural, 

 and other details, brought together in this chapter, in view 



Statistical Details Regarding the Animal Kingdom 



Genera 



I 



si 



Protozoa 



Proteomyxa 



Lobosa 



Mycetozoa 



Heliozoa 



Foraminifera 



(a) terricola 



Foraminifera 



(b) maricola 



Radiolaria 



(a) terricola 



Radiolaria 



(b) maricola 



Sporozoa 



Hgemoflagellata 



Mastigophora 



Infusoria 



Metazoa 



(a) achordata 



Porif era 



Coelenterata 



Echinodermata 



Rotif era 



Mesozoa 



Turbellaria 



(a) rhabdocoela. ... 

 Turbellaria 



(b) tricladida 



Turbellaria 



(c) polycladida .... 



Trematoda 



Cestoda 



Archiannelida 



Nematoda 



Oligochgeta 



Hirudinea 



Polychseta 



Gephy'a-Kinorh'a 



Acanthocephala 



Gastrotrichea 



Chsetosomatida 



Nemertinea 



Polyzoa 



Brachiopoda 



Mollusca 



Crustacea 



Arachnida 



Myriapoda 



Insecta 



Total 



Metazoa 



(b) chordata 



Hemichordata 



Urochordata 



Cephalochordata 



Cyclostomata 



Gnathostomata 



Amphibia 



Reptilia ^ 



Aves 



Mammalia 



Total 



Protozoa-Metazoa achordata 



Grand Total 



54 



118 



33 



8 



