30 PLUMULARIA ATTENUATA. 
short peduncle, by which they spring from the axils of the pinne, open- 
ing on the summit by a wide oblique aperture. 
Off Alligator Reef, from a depth of 88 fathoms. 
This species grows in tufts, numerous undivided stems springing from 
a common base. It is of a rather rigid habit; the pinnez are close set; 
besides the nematophores of the pinne we find on each internode of the 
stem two large, alternately placed, solitary nematophores, and two pairs 
of nematophores which are borne by the lateral process on which the 
hydrothecal ramulus is supported. 
Plumularia macrotheca. 
IB XOVIOUE Lugs. 3, ab 
Trophosome. — Hydrocaulus attaining a height of about two inches, simple, 
fascicled, springing from an entangled mass of fine tubular filaments ; pinnz 
very slender, alternate, composed each of a succession of long internodes 
alternating with short ones, each of the long internodes bearing a hydro- 
theca. Hydrothece deep, tubular, with very slightly everted margin. 
Supracalycine nematophores springing each from a short process which pro- 
jects from the long internode, just below the margin of the hydrotheca, 
one mesial nematophore carried by the same internode at the proximal 
side of the hydrotheca, and another on each of the short internodes. 
Gonosome not known. 
Off Cojima, Cuba, from a depth of 450 fathoms. 
Plumularia macrotheca is remarkable for its long narrow hydrothecx. 
Its very slender pinnz are rather widely set upon the stem, which is fas- 
cicled, and, like other fascicled stems, resolves itself below by the separation 
of its component tubes into a loose plexus of hydrorhizal filaments. 
Plumularia attenuata. 
2 NG ae Figs. 5, 6. 
Trophosome. — Hydrocaulus branched, fascicled below; pinne alternate, 
each arising from a point of the stem close to the distal end of an inter- 
node; internodes of pinnx elongated, becoming abruptly slender in the 
distal two thirds of their length. Hydrothec small, borne by the thicker 
basal portion. 
Supracalycine nematophores springing from tooth-like processes which 
