[frasek] HYDROIDS OF THE VANCOUVER ISLAND REGION 191 



Sertularella pedrensis Torrey 

 PI. XXIX, Fig. Ill 



Sertularella pedrensis Torrey, Hydroids of San Diego, 1904, p. 27. 

 Sertularella pedrensis Fraser, West Coast Hydroids, 1911, p. 70. 



Trophosome. — Colony small, stem with occasional small branches 

 or unbranched, divided into rather regular internodes, each of which 

 bears one hydrotheca; hydrotheca? alternate, free for over half of 

 their length, narrowing distally; margin with three teeth; operculum 

 with three flaps; surface annulated, annulations most noticeable on 

 the adcauline side. As Torrey points out, it bears much resemblance 

 to S. conica but has three teeth instead of four. 



Gonosome.— ''Gonangia ovate, covered thickly and completely 

 with slender spines." (Torrey). 



Distribution.— Prince Rupert, off Clark Rock. 



I have not seen the gonangia. The description and the figure 

 are from Torrey. 



Sertularella pinnata Clark 

 PI. XXX, Fig. 112 



Sertularella pinnata Clark, Alaskan Hydroids, 1876, p. 226. 

 Sertularella pinnata Fraser, West Coast Hydroids, 1911, p. 70. 



Trophosome.— Colonies small but usually growing in dense 

 masses; main stem is divided into short internodes, each of which 

 bears a branch with a hydrotheca in the axil, the branches arranged 

 alternately; the branches often branch again sometimes dichotomously, 

 giving a flabellate appearance to the whole colony; branches divided 

 into short internodes, each of which bears a hydrotheca; the nodes 

 are deeply cut and besides these there are often extra constrictions 

 both on the branch and the hydrotheca; hydrotheca inclined forward 

 and outward so as to appear to be on the front of the stem, distal half 

 or more free; hydrothecae tubular, with a tendency to expansion at 

 the margin; margin with three sharp, strongly marked teeth, two 

 being larger than the third; operculum of three flaps. 



Gonosome. — Gonangia borne in two rows on the front of the main 

 stem and branches, oval, strongly rugose, much distorted; collar 

 small, short; aperture circular. 



Distribution.— -San Juan Archipelago (Fraser); Departure Bay, 

 Northumberland Channel, Dodds Narrows, Pylades Channel, Friday 

 Harbor, Copalis. 



