Ifraser] HYDROIDS OF THE VANCOUVER ISLAND REGION Ï6S 



1. Stem with few branches, either primary or secondary 



H. articulosum 



2. Stem much branched making a dense colony. H. scutum 

 b. Hydrophores borne on distinct pedicels 



1. Delicate branches grow directly from strongly fascicled 



stem, 

 i. Hydrophore pedicel arising from distal end of 



internode H. flexile 



ii. Hydrophore pedicel at proximal end of internode 

 H. reversum 



2. Branches fascicled to some extent 



i. Primary branches short, not much branched 



Gonangia barnacle-shaped H. washingtoni 



ii. Primary branches with numerous branches 



a. Branchlets very numerous throughout the whole 



length of the branches H. densum 



aa. Branchlets at distal end of branches only .... 



H. parvulum 



aaa. Branching rlabellate, gonangia circular, with 



terminal opening H. wilsoni 



aaaa. Branching rlabellate, gonangia oblong-oval. . . . 



H. labrosum 



aaaaa. Branching pinnate, gonangia with two hy- 

 dranths in opening H. halecinum 



Halecium annulatum Torrey 



PI. XIX, Fig. 67 



Halecium annulatum Torrey, Hyd. of the Pacific Coast, 1902, p. 49. 

 Halecium annulatum Fraser, West Coast Hydroids, 1911, p. 46. 



Trophosome. — Delicate stems arising from a stolon, the larger of 

 which are branched irregularly; stem and branches annulated through- 

 out in some cases regularly and in others irregularly; hydrothecae 

 arising from the stem, sessile or nearly so, from the branches on longer 

 pedicels; reduplication common, with long pedicels between the 

 hydrophores. 



Gonosome. — "Female gonothecae broadly ovate, excessively com- 

 pressed, with terminal aperture, single gonophore with numerous ova, 

 surrounded by blastostylar processes reaching to gonothecal wall." 

 (Torrey) . 



Distribution. — Port Renfrew, Ucluelet, Dodds Narrows (Fraser). 



The gonangia were not present in specimens obtained. The 

 description and the figure of these are taken from Torrey. 



Sec. IV, 1914—12 



