70 University of California Publications. [zoology. 



This species closely resembles 8. incongrua in habit. It is 

 distinguished from the latter by the shape and degree of immer- 

 sion of the hydrothecae, the regularity of the interval between 

 branches and the nodes on the stem. It is named in remem- 

 brance of that pioneer worker on Pacific Coast hydroids, 

 Dr. J. B. Trask. 



Selaginopsis group. 



Hydrothecae in more than two rows; many to an internode. 



Selaginopsis cylindrica (Clark). 



Thuiaria cylindrica, Clark, Proc. Ae. Nat. Se, Phil., 1876, XXVIII, p. 



226. 

 SeliHjinopsix eylindrica, Meresehkowsky, Ann. N. H., 1878 (5) II, p. 



445. Calkins, Proc. Bost. Soc. N. H., 1899, XXVIII, p. 362. 



Distribution. Port Orchard, Puget Sd., Townsend Bay, 

 dredged (Calkins). "Port Moller, Alaska Peninsula; 5-17 

 fathoms, sand, August. Hagmeister Island, Bering Sea; beach. 

 Chirikoff Island; beach. Chiachi Islands; 8-15 fathoms, gravel" 

 (Clark). 



No gonosome. One colony. 



Selaginopsis mirabilis (Verrill). 



Diphasia mirabilis, Verrill, Am. Jour. Sc, 1873, (3), V, p. 9. Smith 

 and Harger, Trans. Conn. Ac, 1875, p. 53. Clark, Proc. Ac. 

 Nat. Sc. Phil., 1876, XXVIII, p. 219. 



Selaginopsis mirabilis, Norman, Ann. N. H., 1878, (5), I, p. 192. 



Polyserias hmcksii, Meresehkowsky, Ann. N. H., 1877 (4) XX, p. 228. 



Distribution. Port Orchard, Puget Sd. Hagmeister I., Al., 

 beach; Shumagiu Is., Al. (Clark). White Sea (Meresch.). 

 No gonosome. One colony. 



Hydrallmania group. 



Hydrothecae in one row, several to an internode. 



Hydrallmania distans Nutting. 



Hydrallmania distans, Nutting, Proc. U. S. Nat. Mus., 1899, XXI, p. 

 746. 



Distribution. San Pedro, Cal. Puget Sound (Nutting) . 

 Nutting does not mention the presence of hydrothecae in the 



