61 



Prosobranchiata 



and 400 are terrestrial and air-breathers. They are distributed among 

 the classes as follows: 



Cephalopoda 25 



pulmonata 400 



! Fresh-water 438 



Marine 297 



Heteropoda 28 



Opisthobranchiata 53 



Pteropoda , 25 



scaphopoda 4 



Fresh-water 596 



Marine 377 



MOLLXJSCOIDA. 



Lamellibranchiata 



Braohtopoda 10 



ASCIDIA , 30 



Bryozoa 39 



The remaining divisions of the animal kingdom may be estimated to 

 number nearly as follows : 



ECHINODERMATA (123). 



HOLOTHURroA. 

 ECHINOIDEA . . - 



Crinoidea 



ASTEROIDEA . . 



East 

 coast. 



32 

 50 



2 

 17 



Inte- 

 rior. 



Weat 

 coast. 



4 



18 



Medusae : 



Discophora . . . 



SipJionophora 



Ctenophora 



Polypi 



Hydroidea 



COELENTERATA (144). 



80 



.. 22 



3 .. 



.. 2 



12 .. 



2 



13 .. 



,., 7 



The divisions of Protozoa are well represented in our waters, but the 

 numbers of our Spongiida, Infusoria and Ehizopoda, have not yet 

 been ascertained. 



III. — relations to other realms. 



It has been already remarked that several species of Vertebrata are 

 common to our northern regions and Europe, Asia, etc. Thus, the 



