38 ANTENNELLA GRACILIS. 
ANTENELLA ALitMaN nov. gen. 
Generic CHARACTER. — Trophosome. — Hydrocaulus consisting of simple 
stems, which spring from a congeries of tubular filaments; stems divided 
into internodes, destitute of pinne, and directly bearing the hydrothece. 
Hydrothec with entire margin. Nematophores free and movable. 
Gonosome not known. 
If in a true Plumularia the rachis had never been developed, and the 
pinne had thus come to stand immediately on the hydrorhiza, we should 
have a form with the essential characters of Antennella. 
Antennella gracilis. 
Pi, XXTT igs sO aie 
Trophosome. — Hydrocaulus attaining a height of about an inch, simple 
or with an occasional division near its base, springing in dense tufts from 
a mass of creeping, tortuous, inosculating, and entangled filaments, divided 
into internodes by very oblique joints, and with an intervening obscure hori- 
zontal joint, also generally apparent. Hydrothec borne along the hydro- 
caulus from its distal end to within a short distance of its base, rather large, 
cylindrical, deep, with a circular margin, free for about half their height. 
Supracalycine nematophores borne each on the extremity of a long hollow 
process which flanks the hydrotheca on each side ; mesial nematophores 
usually four between every two hydrothece. 
Gonosome not known. 
Dredged off Carysfort Reef from a depth of 60 fathoms. 
A form nearly allied to the Antennelia gracilis of the present Report has 
been dredged off the British coast by Hincks, who regards it as a variety 
of Phimularia catharina Johnston, and believes it to be identical with the 
Aitennularia cyatlufera of Dana, and with the Sertudaria secundaria of Cavolini. 
That all these belong to the form for which I have constituted the genus 
Antennella, there can, I think, be little doubt. 
Throughout that section of the Plumularids which is characterized by 
its movable nematophores, and of which Plwnularia setacea may be taken 
as the type, the modifications of ramification as expressed in the disposition 
of the hydrothecal or ultimate ramuli admit of being thrown into a series 
whose members present a definite relation to one another. 
Taking as our point of departure such forms as Plumularia setacea of 
