108 THE ROYAL SOCIETY OF CANADA 



SYSTEMATIC DISCUSSION 



The method of classification in this paper does not differ in any 

 respect from that heretofore used. The characteristics of each family 

 and genus are included that the paper itself may he self-contained but 

 in giving these very little change has been made from those given 

 elsewhere. 



The genus Corydendrium, which I have not previously obtained, 

 is used in a different sense to that expressed by some other authors, 

 but an explanation for this is given in the discussion of the genus it- 

 self. Thaumantias as a hydroid genus seems indistinguishable from 

 Clytia and has been dropped. 



A better supply of material has necessitated a change of opinion 

 in the case of some of the species. Diphasia clarœ has turned out to be 

 a young Hydrallmania dis tans. Calycella pygmœa appears to be but 

 a small Calycella syringa. Campanularia pacifica and Obelia gelatinosa 

 are doubtless the same species. Filellum expansum, which has been 

 always considered doubtful, is more so with present day evidence 

 hence it has not been included. 



Further evidence makes it more conclusive that Selaginopsis 

 plumiformis is not distinct from S. cylindrica, that Sertularella denti- 

 fera is not distinct from 5. tricuspidata and that Plumularia palmeri is 

 not distinct from P. lagenifera, hence the former in each of these cases 

 has been left out of the list. In all cases mention is made of these points 

 in the description of the genus or species. 



As in the West Coast paper a complete synonymy, as far as papers 

 bearing on the district are concerned, was given for all species men- 

 tioned, it seems unnecessary to repeat this but a page reference to this 

 paper is given in each case where the species has already been re- 

 ported. Besides this the original reference is always given and in 

 some cases when other papers are mentioned in the discussion this 

 reference is also included in the synonymy. When the species has not 

 previously been reported from this coast, the original reference is given 

 as well as other references to well known papers if such references arc 

 available. 



Sub-order GYMNOBLASTEA 



Hydroids with hydranths unprotected by hydrothecse and 

 gonophores unprotected by gonangia or other structures serving a 

 similar purpose. 



Family Turridae 

 Trophosome. — Hydranths with scattered filiform tentacles. 



