REPORT ON THE HYDROIDA. 
49 
ascertained with accuracy. The largest fragments measured about one inch and a half 
in height, and the pinnately disposed branches attained a length of from one-half to 
three-fourths of an inch. Hydro thecae in all respects like those of the branches are carried 
by the stem along its entire length. The branches, as in all the known species of 
Grammaria, are greatly contracted at their origin. This contracted portion is occupied 
by a simple cavity into which the tubes of the compound branch open. 
Grammaria insignia, n. sp. (PL XXIII. figs. 3, 3«, 3 b). 
Trophosome. — Colony attaining a height of six inches, set with pinnately disposed 
alternate ramuli, which often carry secondary ramuli with a similar disposition. 
Hydrothecse cylindrical, not dilated at the orifice, disposed in four longitudinal series. 
Gonosome not known. 
Locality . — Station 145, off Marion Island ; depth, 50 to 75 fathoms. 
This is a large and handsome species. The main stem is towards its base much 
thicker than the ultimate ramuli, but gradually tapers towards the distal end of the 
colony. The hydrothecae, as in all the known species of Grammaria, are borne both 
along the stem and the branches, and the ultimate ramuli are here, as in every other 
known species, very much constricted at the origin. Grammaria insignis is the only 
species of Grammaria in the collection which has its hydrothecae disposed in four 
longitudinal series. In all the others six such series are present. 
Family SERTULARIDiE. 
Character of the Family. Trophosome . — Hydrothecae in two or more series, with 
the cavity differentiated by a more or less complete floor from that of the hydrocaulus, 
to which their sides are for a greater or less extent adnate. Hydrocaulus not formed 
by inseparably coalesced tubes, of which one is axial and carries the liydrothecae, and 
the others peripheral, definite in number, and destitute of hydrothecae. Hydranths with 
conical hypostome. 
Gonosome . — Gonophores hedrioblastic. 
Sertularia, Linnaeus (in part). 
Sertularia, Linnaeus, Syst. Nat. (Gmel.), p. 3844. 
Generic Character. Trophosome . — Hydrocaulus simple or branched, divided by 
equidistant joints into internodes, each carrying a pair of opposite liydrothecae, 
or two alternate hydrothecae, or a single one. Hydrothecae sessile, in two series, 
(zool. chall. exp. — part lxx. — 1888.) Aaaa 7 
