198 THE ROYAL SOCIETY OF CANADA 



Thuiaria fabricii (Levinsen) 

 PI. XXXIII, Fig. 124 



Sertularia fastigiata Fabricius, Fauna Groenlandica, 1780, p. 458. 

 Sertidaria fabricii Levinsen, Vid. Middel. Naturh. Foren., 1892, 



p. 48. 

 Thuiaria fabricii Fraser, West Coast Hydroids, 1911, p. 76. 



Trophosome. — Stem erect, rather rigid; branches on all sides of 

 the stem, often broken off proximally leaving a stub in each case, 

 distally forming a dense tuft; the density of the tuft is increased by 

 the dichotomous branching which may take place several times; 

 nodes distinct but not regularly placed; hydrothecae usually nearly 

 opposite but often varying in different parts of the stem and branches; 

 hydrothecae narrowing slightly from base to margin, distal portion 

 free; margin with two teeth; operculum with two flaps. 



Gonosome. — Gonangia borne in two rows on the branches, oblong 

 or obovate, with circular aperture and two lateral shoulder spines. 



Distribution. — Puget Sound (Calkins); San Juan Archipelago, 

 Dodds Narrows (Fraser); Alert Bay, Northumberland Channel, 

 off Matia I., off Waldron I., off O'Neale I., off Brown I., Deer Harbor, 

 Griffin Bay, Upright Channel, Port Townsend, Ocean Beach. 



Thuiaria robusta Clark 



PI. XXXIII, Fig. 125 



Thuiaria robusta Clark, Alaskan Hydroids, 1876, p. 227. 

 Thuiaria robusta Fraser, West Coast Hydroids, 1911, p. 76. 



Trophosome. — Stem stout, with deeply-cut internodes; branches 

 also stout arising from all sides of the stem, the proximal often broken 

 off and the distal forming a dense tuft; hydrothecae alternately, not 

 closely placed, proximally almost wholly immersed, distally with a 

 small portion free, long, tubular, very slightly larger at the base 

 than at the margin; margin bi-labiate; operculum with two flaps on 

 the distal hydrothecae and one flap on the proximal. 



Gonosome.— "Gonangia borne in rows on the terminal branchlets, 

 slender with a terminal collar and aperture, and two long, curved spines 

 rising from the antero-lateral corners of the shoulders" (Nutting). 



Distribution.— Albatross Station 2875, N. 48° 30', W. 124° 57', 

 40 fathoms (Nutting). 



I have not found this species in this region. The description and 

 the trophosome drawing are from an Alaskan specimen which had no 

 gonangia. The description and the drawing of the gonangium are 

 from Nutting. 



