C4- University of California Publications. [zoology. 



internodes which vary in length in different branches. Hydrothecae alter- 

 nate, one to each internode; immersed for about halt its length; distal half 

 bent away from the stem, usually narrowing slightly to the orifice, which is 

 furnished with three moderate sub-equal teeth. 

 Gonosome absent. 



Distribution . Mouth of San Diego Harbor, Cal. , 1-9 fathoms. 



This species grows commonly int angles of other hydroids and 

 bryozoa, which may account for the variation iu internodes and 

 hydrothecae. 



Clark found in his Alaska collection what he considered to be 

 a robust variety of 8. fricuspidata Alder. The San Diego species 

 corresponds well to his figures, differing, however, in the greater 

 immersion of the hydrothecae. The aspect of the colony is unite 

 unlike Hincks' figures of S. tricuspidata. So I have thought it 

 best, in the absence of any knowledge of the gonosome, to con- 

 sider it a distinct species. 



Sertularella tenella, Alder. 



Sertularella tenella, Alder, Trans. Tynes. Nat. F. C, 1857, III, p. 113. 

 Hincks, Brit. Hydr. Zobph., 1868, p. 242. Hartlaub, Zool. Jahrb., 

 Abth. Syst. Geogr. u. Biol., 1901, XIV, p, 349. 



Distribution. San Diego, Cal., 9 fathoms. Bare I. (Hartlaub) . 

 ( rreat Britain , between tides to deep water (Hincks) . New Zealand 

 (Hartlaub) . 



Gonosome absent, July 16, 1901. Creeping in profusion over 

 Fucus. Immediately below each opercular piece is a short 

 longitudinal ridge projecting into the cavity of the hydrotheca. 

 Longest stem, 4 mm. long; length of hydrotheca, .4-. 5 mm.; 

 breadth, .25 mm. 



Sertularella turgida (Trask). 



PI. VII, Figs. 59-02. PI. VIII, Figs. 63-69. 



Sertularia twrgida, Trask, Proe. Cal. Ac. Se., 1854, I, p. 113. 

 Sertularella turgida, Clark, Trans. Conn. Ac, 1876, III, p. 259. 

 Sertularella conica, Calkins, Proe. Bost. Soc. N. H., 1899, XXVIII, p. 



359. 

 Sertularella nodulosa, Calkins, ibid, p. 360. 

 Sertularella turgida, Hartlaub, Zool. Jahrb., Abth. Syst. etc., 1901, XIV, 



p. 349. 



Distribution . San Diego, "> fathoms; Catalina I., 42 fathoms; 

 San Pedro, 9 fathoms; Pacific Grove, and San Francisco, Cal.. 



