18 
THE VOYAGE OF H.M.S. CHALLENGER. 
Their height is about half that of the hydrophore and their width is about one-third of 
their height. The orifice is quite even. They are attached to the stem by a narrow 
continuation of the base, which however is never so elongated as to form a true peduncle. 
The Challenger specimen has a height of about four inches. The ramuli which are 
given off from the main stem are sometimes simple, sometimes once or twice branched. 
Among the characters which indicate the close affinity of Diplocyathus with Halecium 
must further be mentioned the wreath of minute brilliant points which surrounds the 
limbus of the hydrophore. Judging from Hincks’ figure of Ophioides a similar feature 
would seem to be present in that genus, and indeed is scarcely ever wanting in any species 
of Halecium or of the allied genera. 
The hydranth is large and furnished with about twenty-six tentacles. 
Family CAMPANULARIDiE. 
Character of the Family. Trophosome. — Hydrothecse borne by peduncles, cam- 
panulate or tubular ; hydrocaulus not enveloped by peripheral tubes. 
Gonosome. — G-onophores planoblasts or hedrioblasts. 
Campanularia, Lamarck (in part). 
Campanularia, Lamarck, Hist. Anim. sans Vert., ed. 2, vol. ii. 
Generic Character. Trophosome. — Hydrotliecae pedunculate, campanuliform, with 
serrate or entire margin destitute of operculum, and with the cavity distinctly 
differentiated by a perforated diaphragm from that of the peduncle, peduncle springing 
from the sides of a simple or ramified, free or adherent hydrocaulus. Hydranths with 
a trumpet-shaped hypostome. 
Gonosome. — Gonophores adelocodonic, never issuing from beneath the cover of the 
gonangium. 
The genus Campanularia , as originally defined by Lamarck, included several forms 
which the closer examination to which they have been since subjected has shown to be 
more correctly distributed under separate generic groups. Even among those species in 
which the hydro thecse present the true campanulate form, there are some in which the 
gonophores are sedentary sacs without any obvious medusiform conformation, and others 
in which the gonophores are true medusiform planoblasts. 
A difference of this kind is of sufficient importance to justify its being made the 
grounds of a generic separation, and I believe with Mr. Hincks that it will be better to 
limit the genus Campamdaria so as .to make it include only those species in which, with 
the trophosome presenting the characters here enumerated, the gonophores are destitute of 
obvious medusiform structure. So limited, it will include the greater number of the species 
