152 THE ROYAL SOCIETY OF CANADA 



? Obelia fragilis Calkins 



Pi. XVI, Fig. 52 



Obelia fragilis Calkins, Puget Sound Hydroids, 1899, p. 355. 

 Obelia fragilis Fraser, West Coast Hydroids, 1911, p. 39. 



Trophosome. — "Hydrocaulus clinging and never erect. Stem 

 polysiphonic long, flexuous, branched at regular intervals, branches 

 also comparative long and flexuous, slightly ringed at the base and 

 with 4 rings above each branch. Hydrothecae deeply bell-shaped; 

 the chitinous periderm is exceedingly delicate and easily wrinkled 

 or folded. Hydrothecae placed alternately at some distance apart. 

 Margin sinuous. Stems short and annulated throughout, a large 

 hydrotheca in the axil of each branch." (Calkins). 



Gonosome. — Unknown. 



Dimensions. — "Length of colony 30 mm.; length of branches 

 9 mm.; distance between branches 1-5 mm.; length of hydrotheca 

 •5 mm., width of margin -4 mm., number of tentacles 22-24." (Calkins). 



Distribution. — Dredged in Port Townshend Harbor on Aglao- 

 phenia struthionides . (Calkins). 



I do not know this species and hence have given Calkins' de- 

 scription and figures throughout. 



Obelia gracilis Calkins 

 PI. XVI, Fig. 53 



Obelia gracilis Calkins, Puget Sound Hydroids, 1899, p. 353. 

 Obelia gracilis Fraser, West Coast Hydroids, 1911, p. 39. 



Trophosome. — Colony small, stem slender, reaching a height of 

 20 mm., either entirely without branches or with few small branches; 

 stem somewhat zigzag with one or two hydranth pedicels given off 

 at each bend; a branch and one hydranth pedicel may be given off 

 at each of the lower nodes, a little higher up two hydranth pedicels, 

 one much longer than the other but bearing a smaller hydrotheca, 

 while at the more distal nodes there is usually but one pedicel to the 

 node; sides of the hydrotheca slightly convex, margin entire. 



Gonosome. — Gonangia take the place of the lower hydrothecae, 

 generally but one hydrotheca at a node is so replaced but occasionally 

 both of them are. The gonangia are rather slender, increasing in 

 size from the base upwards, either smooth or somewhat irregular but 

 scarcely corrugated; the distal portion ends in a distinct collar. 



Distribution. — Scow Bay, Port Townshend (Calkins); San Juan 

 Archipelago (Fraser); San Juan Archipelago, Port Townshend. 



