NO. 1 fraser: hydroids 45 



dichotomous effect. When a hydrophore terminates a branch, the pedicel 

 is of considerable length, otherwise it is sessile. Hydrophore scarcely 

 flaring. 



Gonosome. — Not observed. 



Distribution. — South of La Plata Island, 45-55 fathoms; San Fran- 

 cisco Bay, 3-8 fathoms; Pacora Island, 15-25 fathoms; Secas Islands, 

 25 fathoms; east of islands off Navidad Head, 25-35 fathoms. 



This species bears some resemblance to H. tenellum, but the stem 

 and branches are much less annulated or wrinkled, the cauline hydro- 

 phores are sessile and they lack the strong flare so evident in H. 

 tenellum. 



Halecium washlngtoni Nutting 



Halecium geniculatmn Nutting^ Hyd. of Alaska and Puget Sound, 



1899, p. 744. 



Halecium washingtoni Nutting^ Am. Nat., XXXIV, 1901, p. 789. 



Fraser^ Hyd. of Vancouver Island, 1914, p. 

 169. 



Distribution. — In the channel between Narborough and Albemarle 

 islands, 70 fathoms; Thurloe Point, 8-10 and 30 fathoms; South Bay, 

 Cerros Island, 10-15 fathoms. 



Genus OPHIODISSA 



Ophiodissa laxa, new species 

 Plate 10, Fig. 50 



Trophosome. — Colonies clustered, 15 mm.; stem strongly geniculate 

 or somewhat dichotomously arranged. Each portion of the stem that 

 corresponds to an internode in the regular type is slender, much elon- 

 gated, and much the same size throughout, with one or two annula- 

 tions at the base given off a short distance below the hydrophore of the 

 preceding portion. There may be another hydrophore or branch given 

 off from the opposite side, to give the dichotomous effect. The hydro- 

 phore is definitely flaring. 



Tentacular organs large, tubular, commonly one from each pedicel 

 or internodal portion of the stem. 



Gonosome. — Not observed. 



Distribution. — Secas Islands, 15 and 25 fathoms. 



