[fraser] HYDROIDS OF THE VANCOUVER ISLAND REGION 115 



Key to species of Bimeria found in the Vancouver I. region. 



A. Branches slender, but little wrinkled B. gracilis 



B. Branches stout, wrinkled throughout B. robusta 



? Bimeria gracilis Clark 

 PI. IV, Fig. 7 



Bimeria gracilis Clark, Hydroids of the Pacific Coast, 1876, 



p. 252. 



Bimeria gracilis Torrey, Hydroids of San Diego, 1904, p. 6. 



Bimeria gracilis Fraser, West Coast Hydroids, 1911, p. 22. 



Trophosome. — Stem fascicled, growing from a creeping hydrorhiza, 

 reaching a height of 35 mm.; branches rather short and delicate, 

 seldom spreading but taking nearly the same direction as the stem; 

 perisarc mostly smooth but slightly ringed or wrinkled at the base 

 of each pedicel; hydranth with 10-11 tentacles. 



Gonosome. — Gonophores borne on the branches singly or in pairs; 

 sporosacs oval; pedicel short, almost suppressed. 



Color. — Very little color apparent in either stem or hydranth. 



Distribution. — Nanoose Bay, off Clarke Rk., off West Rocks, 

 Dodds Narrows, Gabriola Pass, Gabriola Reefs, Ruxton Passage. 



The specimens obtained do not show the annulations at the base 

 of the pedicels so distinctly as indicated by Clark but apart from this 

 they answer to his description and I have little doubt that they belong 

 to the same species. 



Bimeria robusta Torrey 

 PI. Ill, Fig. 5 



Bimeria robusta Torrey, Hydroida of the Pacific Coast, 1902, 



p. 29. 



Bimeria robusta Fraser, West Coast Hydroids, 1911, p. 22. 



Trophosome. — "Hydrorhiza encrusting; stems and larger branches 

 stout, polysiphonic. Colony may be 13 cm. long, largest branches 

 4 cm., or even 6 cm. long. The latter arise irregularly; hydranth 

 pedicels from these or from secondaries which are always short (6-8 

 mm.) and may bear 2-4 hydranths; all branches rather closely 

 associated; perisarc wrinkled throughout, investing the hydranth 

 body and possibly the base of the tentacles. Hydranths fusiform 

 with conical proboscis, the largest with 11 tentacles, rarely 12, in one 

 case 16. Five tentacles are longer and often stouter than the others, 

 subequal, suberect and belong to the first whorl. The tentacles of 

 the second whorl alternate with these, are shorter, subequal and bend 

 downward." (Torrey). 



Sec. IV, 1914—9 



