164 THE ROYAL SOCIETY OF CANADA 



Halecium articulosum Clark 



PI. XIX, Fig. 68 



Halecium articulosum Clark, New England Hydroids, 1876, p. 63. 

 Halecium articulosum Nutting, Hydroids of Woods Hole, 1901, p 357. 

 Halecium articulosum Jàderholm, Northern and Arctic Invert., 



1909, p. 58. 



Trophosome. — Stem coarse, fascicled, primary branches scarce 

 but long, hence the colony has a very loose appearance, ultimate 

 branches pinnately arranged, white, distinct from the larger branches 

 and main stem which are dark brown; internodes short and getting 

 shorter towards the end of the branches, where they may be as broad 

 as long; hydrothecse sessile, alternately arranged, one distally, on 

 each internode. 



Gonosome. — Female gonangia large, obovate, borne in rows on 

 the upper side of the branches, aperture lateral but near the distal 

 end. "Male gonangia are oblong, subcylindrical, sessile" (Clark). 



Distribution. — Jumbo Channel (from University of Washington). 



Only female colonies were obtained. 



Halecium corrugatum Nutting 



PI. XIX, Fig. 69 



Halecium corrugatum Nutting, Hyd. from Alaska and Puget Sound, 



1899, p. 745. 

 Halecium corrugatum Fraser, West Coast Hydroids, 1911, p. 47. 



Trophosome. — Colony creeping, stem bearing but one hydrophore, 

 or branching sufficiently to bear as many as 3 or 4; these arranged 

 very irregularly on the stolon; the stolon is not annulated but the 

 pedicels are distinctly and regularly annulated throughout; margin 

 everted but not very strongly. 



Gonosome. — (Not previously described) Gonangia borne directly 

 on the stolon with scarcely a sign of pedicel; the proximal half is 

 larger, after this the gonangium narrows gradually almost to the distal 

 end when the diameter is again increased; aperture occupying all 

 the distal end; surface smooth. 



Distribution. — Puget Sound (Nutting) ; Clayuquot Sound, Na- 

 noose Bay, north of Gabriola Island, off Matia I. 



Halecium densum Calkins 



P. XIX, Fig. 70 

 Halecium densum Calkins, Hyd. from Puget Sound, 1899, p. 343. 

 Halecium densum Fraser, West Coast Hydroids, 1911, p. 47. 



