NO. 28 NEW HYDROIDS FRASER 5 



nodes, or at most one on each. The remainder of the hydrocladium 

 is divided into internodes by alternate transverse and oblique nodes, 

 the internodes being alternately thecate and nonthecate ; the thecate 

 internode has an oblique node proximally and a transverse node dis- 

 tally, the nonthecate internode with a transverse node proximally 

 and an oblique node distally. Hydrotheca nearly equal in depth and 

 breadth ; the abaxial border is regularly convex but the adaxial border 

 has a distinct concavity. Margin entire. There is a median nemato- 

 phore at the base of the hydrotheca, one near the distal end of the 

 thecate internode and one on the nonthecate internode ; there is a 

 pair of supracalycine nematophores, the end of each fitting into the 

 concavity of the superior border of the hydrotheca 



Gonosome. — Not observed. 



Holotype. — U.S.N. M. no. 43291. 



Distribution. — North of Puerto Rico, lat. i8°24'3o" N., long. 65° 

 38'3o" W. ; 9 fathoms. 



HALICORNARIA LONGICAUDA Nutting 



Plate 2, fig. 8 



Halicornaria Io)igicaiida Nutting, American hydroids, U. S. Nat. Mus. Special 

 Bull. 4, pt. I, p. 127, 1900. 



Trophosome. — See Nutting's description. 



Gonosome. — Gonangia arising from the face of the cauline inter- 

 nodes, just below the hydrocladial processes ; sessile, truncated-oval, 

 with a smooth surface. No special protective structures. 



Distribiifioii. — North of Puerto Rico, lat. i8''24'3o" N., long. 65° 

 38'3o" W. ; 9 fathoms. North of Culebra island, lat. i8°i9'io" N., 

 long. 65°i9'4o" W. ; 10 fathoms. 



HIPPURELLA ELEGANS, n. sp. 



Plate 2, fig. 9 



Trophosome. — Colony 35 cm high ; stem fascicled throughout the 

 greater portion of its length; 15 cm or more of the basal portion is 

 without branches or hydrocladia ; then long slender branches are given 

 ofif, usually in nearly opposite pairs but sometimes singly, no two, or 

 two pairs, in succession, being in the same plane ; the whole distal 

 portion, therefore, has a graceful, bushy appearance. There is no 

 indication of nodes in the stem or in the proximal portion of the 

 branches and but little in the distal portion. The hydrocladia are 

 arranged regularly alternately on the branches, making an angle of 



