HYDEOIDS OF THE HAWAIIAN ISLANDS. 
939 
Family CERATELLIDtE. 
Trophosome. — Colony branched. Skeleton in the form of a chitinous network with slight bracket- 
like or tubular hydrophores serving as a support for the bases of the hydranths. Hydrocaulus in the 
form of network of anastomosing tubes, the whole inclosed in a common ectoderm layer. 
Gonosome. — Gonophores medusoid; fixed and arising directly from the hydrocaulus. This defi- 
nition is practically the same as that given by Prof. W. Baldwin Spencer in his “On the structure of 
Ceratella fusca (Gray).” (Transactions of the Royal Society of Victoria, 1891. Reprint, pp. 1-24.) 
Genus CERATELLA. 
Trophosome. — “Colony irregularly branching; more or less expanded in one plane; growing from 
a creeping base. Main stem flattened, branches rounded and beset with bracket- like hydrophores.” 0 
Ceratella fusca Gray. 
But a single specimen of this species was found. 
Locality. — Station 4072, north coast of the island of Maui, 56 fathoms. 
CerateUa fusca, Gray, Proc. Zool. Soc„ Vol. VIII, Nov., 1868, 577. 
Family EUDENDRID^E. 
Trophosome. — Colony branched, stem fascicled. Hydranth with a single circlet of filiform tentacles 
and a trumpet-shaped proboscis. 
Gonosome. — The male gonophores form a verticil just beneath the tentacles of the hydranth, each 
gonophore having 2 to 4 chambers in linear series. Female gonophores not in regular verticils and 
usually clustered just beneath the tentacles on the bodies of the hydranths. The hydranths in both 
sexes are often more or less degenerated when bearing gonophores. 
Genus EUDENDRIUM. 
There being but one genus recognized in the family its characters are as given above. 
Eudendrium rameum (Pallas). 
Several specimens of Eudendrium were secured that I am unable to separate from this well-known 
form. They show the characteristic dendritic habit of growth of this species, but do not attain the 
size of British specimens. The gonosome, female, is present and shows no point of differentiation 
from E. rameum. 
Localities. — Station 4077, off the coast of the island of Maui, 99 fathoms; station 4135, off the coast 
of the island of Kauai, 225 fathoms. 
This species is of Holarctic distribution, being found off the coasts of Europe, the Arctic region, 
and in the Pacific as far south as Australia. 
Tubularia ramea Pallas, Elenchus Zoophytorum, 83, 1116, 1766. 
PEudendrium capillare Alder. 
A small specimen without gonosome is very doubtfully referred to this species. The colony is 
somewhat larger than British specimens. 
Locality. — Station 3854, off the south coast of the island of Molokai, 134 fathoms. 
? Eudendrium capillare Alder, Catalogue of the Zoophytes of Northumberland and Durham, p. 15, 1857. 
iOp. cit., p. 20. 
