260 iS'. F. Clark — Hydroids of the Pacific Coast. 



is on the inner margin of the rim midway between the other two. 

 Gonothecae, arising in the axils of the hydrotheca?, are large and of 

 two forms ; the larger form, similar to the gonotheea of Sertu- 

 larella polyzonias Gray (Linn.), is obovate, sessile, armed with a 

 few stout, blunt spines around the distal end, aperture, terminal 

 and at the outer end of a small cylindrical process formed by a 

 constriction or a very sudden tapering near the extremity and 

 surrounded by a number of the largest spines ; the smallei' form is 

 supplied Avith about twice as many spines as the larger foi'm and is 

 shorter and proportionally broader, the broadest portion being nearer 

 to the distal end ; this variation in form undoubtedly indicates a sexual 

 difference, the smaller form proba1>ly being the male find the larger 

 the female gonothecje ; both forms have the surface more or less 

 roughened by transverse Avrinkles. Length of largest specimen, 

 38""". 



Bay of San Francisco, Monterey, Tomales Point, Cal„ on mollusca 

 and alga^, — Trask ; Santa Ci-uz, Bay of Monterey, Cal.,— Dr. C. W. 

 Anderson ; San Diego, Cal., — D. C. Cleveland ; Vancouver Island, 

 — J. M. Dawson. 



The nearest ally of S. turglda is the ^S. polyzonias of Gray, to 

 which in many respects it bears a striking resemblance. 



Hydrallmania Franciscana Clark (Trask). 



Plumularia Franciscana Trask, Proc. Cal. Acad, of Nat, Sci., vol. i, p. 113, PI. IV, 



fig. 3. 

 Plumularia gracilis Murray, Ann. and Mag. of Nat. Hist, for April, 1800, p. 251, 



PI. XII, fig. 1. 



Trask and Murray both had representatives of a species which they 

 referred to the genus Plwnularia and whicli, from their descriptions 

 and figures, undoul)tedly belongs to Hinck's genus Ilydmllmania, 

 though at the time their descriptions were published, this genus had 

 not been recognized. This sjiecies is certainly very close to II. 

 falcata of Hincks, but Murray, who had an opportunity of comparing 

 the two, says they are distinct. 



Unfortunately we have had no specimens. 



Bay of San Francisco, Cal., among rejectamenta on the beach, 

 —Trask. 



