114 THE PLUMULARID.E. 



late; hydrocladia distant, slender, divided iuto very long interuodes which are bent forward above 

 the top of each hydrotheca, and then reassume the general direction of the hydrocladiuin ; inter- 

 nodes divided by numerous septal ridges, which appear to surround the axial cavity. Hydrotheca' 

 distant, long and deep, cylindrical, with the margin slightly expanded, with a single median 

 anterior tooth, and five or six small lateral teeth on each side; supracalyciue nematophores long 

 and tubular, overtopping the hydrotheca; mesial nematophore short, curved, slender, free for 

 nearly its entire length, and with the side toward the hydrotheca open; a cauliue neuiatophore in 

 the axil of each hydrocladium, and another near the middle of each interuode of the stem; below 

 the hydrocladiate portion the stem is armed with a row of regularly disposed nematophores 

 along its anterior surface. 



Oonosome. Gouaugia borne singly on the stem near the axils of the hydrocladia; oblong- 

 ovate, with a lunate latero-teriuinal orifice; phylactogouia shaped like stag's horns, with three 

 nematophorous branches arching over the gouangia. 



Distribution. Oft' Pacific Eeef, Florida; depth, 283 fathoms; Albatross Station 2601, lat. N. 

 34 39', long. W. 75 33'; depth, 107 fathoms. 



C. ilolitJiotliectt is one of the smallest species of the genus, and differs from most of the others 

 in having a uoufascicled stem. In all of the specimens thus far found the bare portion of the stem 

 is very long as compared with the part bearing the hydrocladia. 



Type. In the Museum of Comparative Zoology, Cambridge, Massachusetts. 



CLADOCARPUS FLEXUOSUS, new species. 

 (Plate XXVII, figs. 11-13.) 



Tropho&ome. Colony (in incomplete specimen) unbranched, attaining a height of 3 inches; 

 stem not fascicled; hydrocladia alternate, very long and slender, sinuous; internodes very long 

 and slender, sinuous, with a few septal ridges opposite the hydrotheca and at the ends. 

 Hydrothec;v distant, very large, long and slender, shaped like lengthened cones, the anterior 

 profile being almost straight; margin with a strong anterior median tooth, and a number of 

 small lateral sinuatious; intrathecal ridge not evident; supracalycine nematophores slender, 

 tubular, overtopping the hydrotheca; mesial nematophore short, slender, free, barely reaching 

 the- level of the bottom of the hydrotheca. 



Gonosome. Not known. 



Distribution. Albatross Station 2384, lat. N. 28 45', long. W. 88 16'; depth, 940 fathoms. 



This very graceful and striking form reminds one most of C. dolichotheca Allman, from which 

 it differs in having the hydrotheca- shaped like lengthened cones instead of being nearly tubular. 

 It differs from C. tennis Clarke in having the anterior profile of the hydrotheca straight instead of 

 concave. The single specimen secured by the Albatross came up from a depth of 940 fathoms, one 

 of the deepest hauls which have produced Plmnulariaus. 



Type slides. Cat. No. 18679, U.S.N.M.; Cat, No. 15381, Mus. State Univ. Iowa; also in the 

 collection of the author. 



CLADOCARPUS TENUIS Clarke. 



(Plate XXVIII, figs. 1, 2.) 

 Claflocarpus tennis CLARKE, Bull. Mus. Comp. Zool., 1877, V, No. 2, p. 247, pi. v. 



Trophosome. Hydrocaulus attaining a height of an inch and a half, very delicate, pale straw- 

 color, the lower portion bearing a row of nematophores, the upper portion giving rise to branches 

 arranged alternately, and with three or four very obliijue internodes just below the branched 

 portion; the branches or pinna' undivided. Hydrothecti- deep, slender, tubular, smallest in the 

 center and tapering both ways, largest at the distal end, a crenate rim and a large rectangular or 

 obtusely pointed median tooth; each hydrotheca overarched by the portion of the pinna which 

 intervenes between it and the next. Supracalycine nematophores prominent, extending above 

 the edge of the hydrotheca; mesial nematophore of about the same size of the supracalyciue, and 

 attached to the enlarged portion of the pinna .just below the hydrotheca. The piniue are orna- 

 mented with a great number of internal chitinoiis ridges. 



