﻿166 PROCEEDINGS OF THE [April, 1857. 



EUDENDRIUM. Ehrenberg. 



Medusae but little known. According to DalyelPs account, 

 they seem to be mere cysts, serving to protect the planules during 

 their growth, and aTe developed on the twigs which bear the 

 polyps, but usually near the bases of the latter. 



The polypidorn is branching and horny, attaining considerable 

 size. The polyps are distinguished from those of the larvae of 

 Hippocrene by a slightly expanded base, bearing the circle of ten- 

 tacula, and by having the oral prominence, a very contractile 

 organ, sometimes separated by a slight constriction from the ex- 

 panded base. The twigs which bear the polyps are more or less 

 annulate. 



Distribution. — Coasts of Great Britain and South Carolina. 



EUDENDRIUM RAMOSUM. 



If this species be not identical with the E. ramosum of Europe, 

 I do not know by what characters to distinguish it since I have 

 never been able to observe its medusa-buds. 



The rose-colored polyps are quite small, and have about eight 

 tentacula on a base, which is not much expanded, but I do not 

 describe from the fully developed polyp. The mouth in the 

 young polyps, at least, is more or less prominent and proboscidi- 

 form. sometimes assuming a sphericai shape, being then distin- 

 guished by a constriction from the tentacular base. The branchlet 

 on which each polyp is borne is annulate near the base of the 

 polyp. 



The polypidorn is composed of slender branching dark-colored 

 tubes, about six inches, sometimes perhaps even more in length, 

 on which the polyp-branchlets are not disposed with much regu- 

 larity. 



It is evident that the E. ramosum of Van Beneden and the E. 

 ramosum of Dalyell, are very different species from that of John- 

 ston, with which, for the present, I consider this identical. 



I observed, on one occasion, a singular deformity in a polyp of 

 this species. The body of the animal was much enlarged below 

 the bases of the somewhat stunted tentacula. There was no pro- 

 boscidiform prominence to the mouth. The turgescence was so 

 evidently occasioned by something within, that after it had re- 

 mained a day or two in a jar of salt-water, I slit the polyp open 

 beneath the microscope and found that it contained a reddish 

 granular thread, coiled in such a manner as to remind one of the 



