THE pLUMULARiD-flj. 71 



Distribution. Albatross Station 2200, off' Marthns Vineyard, 40 fathoms. 



This very distinct species recalls the ln<jcn if cm group of the genus I'liniu/laria in the numerous 

 thickened internal ridges in the hydrocladia, but is almost unique in the possession of a peculiar 

 support of the hydrocladia effected by a notable thickening of the perisarc on the under or 

 external surface of each liydrocladiuin. The processes of the stem which support the hydrocladia 

 are unusually short, and each bears a swollen protuberance upon its upper surface. 



Type sliilfs. Cat. No. 18559, U.S.N.M.; Cat. No. 11092, Mus. State Univ. Iowa; also in the 

 collection of the author. 



ANTENNULARIA GENICULATA, new species. 

 (Plate X, lisa. 3,4.) 



Trophosome. Colony attaining a height of 5 inches, unbrauched; stem with canaliculated 

 crrnosarc, divided into internodes, and bearing scattered hydrociadia on processes which have a 

 distinct tooth-like projection on the upper surface; distal portion of stem geniculated; hydrocladia 

 borne on long, stout processes scattered over the surface of the stem, but often showing a tendency 

 to a verticillate arrangement; tirst internode very short, without hydrotheca; second long, 

 hydrothecate, the remainder of the liydrocladiuin being composed of alternating hydrothecate and 

 intermediate internodes, the latter being the shorter. Hydrothecic subconical, about as deep as 

 wide, and borne just below the middle of the internode; nematophores rather large, supracalycine 

 pair present; a mesial nematophore at base of each hydrotheca, one or two on each intermediate 

 internode, and a few cauline nematophores scattered rather sparsely on the stem, there being one 

 or two in the axil of each hydrocladium. 



Gonosome. Gronangia borne in pairs in the axils of the hydrocladia, large, ovate, with the 

 distal end turned to one side and the aperture directed lateially. 



Distribution. Albatross Station 2415, lat. JS". 30 44', long. W. 79 26', 440 fathoms; Albatross 

 Station 2C67, lat. N. 30 53', long. W. 79 43', 273 fathoms; Albatross Station 2008, lat. K 30 59', 

 long. W. 79 39', 2!)4 fathoms; Albatross Station 2009, lat. N. 31 09', long. W. 79 34', 352 fathoms. 



This species illustrates the complete intergradatiou, so far as distribution of hydrocladia is 

 concerned, between the genera Antennularia and Antennopsis. Indeed, if only the distal portion 

 of a colony were examined one would be inclined to call it a Plumularia, for the hydrocladia are 

 often pinuately arranged toward the end of the stem. 



Type slides. Cat. Nos. 18501, 18502, U.S.N.M.; Cat. Nos. 11689 11090, Mns. State Univ. Iowa; 

 also in the collection of the author. 



ANTENNULARIA PINNATA, new species. 

 (Plate X, figs. 5,6.) 



Trophosome. Hydrocaulus unbrauched or sparsely branched, attaining a height of about 3 

 inches; stem with few ca-nosarcal canaliculi; in some specimens these seem to be largely obliter- 

 ated, as if the cu-nosarc had been broken down by maceration, in others they are as prominent as 

 usual in this group; hydrocladia borueon moderately long processes from the stem, pinnate, alter- 

 nate, or scattered (according to age of specimen or the part of the colony examined), composed of 

 regularly alternating hydrothecate and intermediate internodes, divided by well-marked nodes, 

 often accompanied by internal thickenings at the ends of the iuternodes; two nodes between 

 proximal hydrotheca and the stem. Hydrotheca' distant, cup shaped, about as deep as wide, 

 situated near the middle of the internodes; nematophores large, a supracalycine pair, a mesial 

 one below each hydrotheca, and another on each intermediate internode; a pair of cauline uema- 

 tophores in the axil of each hydrocladium, and others scattered over the stem. 



Gonosome. Not known. 



Distribution. U. S. Fish Commission Station 872, lat. N. 40 00', long. W. 70 24'; depth, 86 

 fathoms; Station 949, lat. N. 40 03', long. W. 70 31'; depth, 100 fathoms. 



This species is darker colored than most of the genus, being dark brown, lightening to horn 

 color in the distal parts. The hydrocladia are more rigid than usual, and are often arranged 



