252 S. F. Clark — Ilydroids of the Pacific Coast. 



Bimeria (?) gracilis, sp. nov. 

 riate XXXVIII, figure 3. 



Stems clustered, rooted by a creeping stolon, erect, simple, delicate, 

 not divided by distinct joints, thickly branched ; branches suberect, 

 the larger ones reaching to the end of the stem and resembling the 

 main stalk, the smaller ones bear but one or two hydranths and are 

 also unjointed; perisarc extending over the hydranths and partially 

 covering the tentacles, annulated at the base of each branch and 

 branchlet. Sporosacs developed from the hydrophyton, a single one 

 at the base of each hydranth-bearing branchlet, oval or ovate, sup- 

 ported by a short peduncle consisting of one or two annulations. 

 Hydranths large, tapering uniformly from the distal end to the base, 

 provided with about ten or twelve tentacles and with a large, 

 rounded or slightly conical proboscis. Height of best specimen, 

 55"'"'. 



Collected on the jtiles of wharves at San Diego, Cal., by Dr. E. 

 Palmer, 18'75. 



Our specimens were not in a good condition when they arrived, 

 having been crowded in a tin can with many other things, which 

 pressed them all out of shape, and the quantity of alcohol not being 

 sufficient to preserve so much animal matter, the hydi-oids suffered 

 considerably; the hydranths and sporosacs especially were in a very 

 worn and mutilated state. It is not easy to determine just how far 

 the perisarc extends upon the hydranth, but it certainly covers tlie 

 body of the latter, and it must, I think, be developed over a portion 

 of the tentacles, for after soaking them in a dilute solution of caustic 

 potash for forty-eight hours the tentacles still retained their normal 

 position, nor did they show any decrease in size. The potash seemed 

 to act very slowly, for after being in the warm solution forty-eight 

 hours the hydranths were not entirely dissolved out. The fact of 

 the tentacles being unaftected would seem to indicate that they are 

 entirelv protected by chitin, but tentacles so protected would be of 

 little or no use to the animal, and I think it more j)rol)able that the 

 distal portions are free and may be contracted into the basal covering. 

 It is impossible to determine from our specimens how the tentacles 

 are held, whethei- in a single erect verticil as in Garveia or with 

 each alternate tentacle depressed, as in Bimeria vestita of Wright. 

 With such imi)erfect data I feel some doubt about placing this species 

 in the genus Bimeria, and only do so provisionally. 



