[92 THE ROYAL SOCIETY OF CANADA 



Sertularella polyzonias (Linnaeus) 

 PI. XXX, Fig. 113 



Sertularia polyzonias Linnaeus, Syst. Nat., 1758, p. 813. 

 Sertularella polyzonias Fraser, West Coast Hydroids, 1911, p. 70. 



Trophosome. — Stem rather slender; branching very irregular 

 with a tendency to be alternate, branches long and like the stem 

 flexuous; the branches may be unbranched or may branch extensively; 

 nodes often appear at regular intervals, each internode bearing a 

 hydrotheca; hydrothecae alternate, rather distant, large, tapering 

 but slightly towards the distal end, the distal half or more free; 

 margin with four teeth that are not very distinct; operculum of four 

 flaps. 



Gonosome. — Gonangia large, oval; margin with four distinct, stout 

 spines or teeth; surface strongly and regularly rugose. 



Distribution. — San Juan Archipelago (Fraser); Clayuquot Sound, 

 Dodds Narrows, Gabriola Pass, off Matia I., off Waldron I., Friday 

 Harbor. 



Sertularella rugosa (Linnaeus) 



PI. XXX, Fig. 114 



Sertularia rugosa Linn.eus, Syst. Nat. 1758, p. 809. 

 Sertularella rugosa Fraser, West Coast Hydroids, 1911, p. 70. 



Trophosome. — Colony small; stems usually unbranched, divided 

 into regular internodes, each of which bears a hydrotheca; besides 

 the regular nodes there are several other annulations or constrictions 

 in the stem; hydrotheca' alternate, rather distant, fusiform, distinctly 

 and markedly rugose, but the distal fourth or more is smooth; margin 

 with four teeth, not very strongly marked; operculum with tour 

 flaps. 



Gonosome. — Gonangia oval, rugose; margin with four teeth. 



Distribution. — Puget Sound (Nutting); Dodds Narrows, Gabriola 

 Pass, Friday Harbor. 



Sertularella tanneri Nutting 



PI. XXX, Fig. 115 



Sertularella tanneri Nutting, American Hydroids, pt. 2, 1904, p. 81. 

 Sertularella tanneri Fraser, West Coast Hydroids, 1911, p. 70. 



Trophosome. — Stem rather slender, not rigid, branching ir- 

 regularly, the branches having the same appearance as the main stem; 

 stem and branches divided into regular internodes by oblique nodes, 

 above which are annular depressions of the stem; hydrothecae alternate, 



