284 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 4 



may give off short, secondary branches. The stem is divided into regular 

 internodes, with the diameter at the base of each internode less than that 

 at the distal end ; the nodes are strongly marked but are not flanked with 

 septa. From each internode, near the distal end, a hydrocladium is given 

 off, the angle between the process and the stem being acute. The hydrocla- 

 dial process is longer than usual in Plumularia. The hydrocladium is 

 short ; the first internode is short and is athecate ; the second one is much 

 longer and is thecate ; after this athecate and thecate internodes appear in 

 regular alternation. The hydrotheca appears in the distal one-third of the 

 internode. The internodal septa are very noticeable ; each node is flanked 

 on each side by a septum, except that in the first, athecate internode, as 

 it is so short there is but 1 septum. Besides these, on the thecate internode, 

 there is a septum about midway between the hydrotheca and the proximal 

 node, and 1 at the base of the hydrotheca. Besides the regular supracaly- 

 cine nematophores, there are 2 mesial nematophores on the first thecate 

 internode, and 1 on each of the following internodes; there is none on 

 the first, athecate internode. There is a nematophore at the axil of the 

 hydrocladial process and 1 on each cauline internode on the side opposite 

 the hydrocladial process, approximately one-third of the distance from 

 the proximal node. 



Distribution. — Station 1472-42, north of Winchester Bay, Ore., 26- 

 58 fathoms. 



Remarks. — The species is much similar to P. flabellum, reported by 

 Allman from Marion Island, south of South Africa, 50-75 fathoms (All- 

 man, G. J., -'Report on the Hydroida," Challenger Reports, XX, 1883, 

 p. 19), but there are several noticeable differences. P. flabellum is strong- 

 ly fascicled, the cauline internodes are uniform in diameter throughout, 

 there may be 2 hydrocladia from 1 internode ; there is a nematophore near 

 the distal end of the hydrocladial process and a mesial on the first thecate 

 internode (i.e., if one may judge from Allman's figures) ; the remainder 

 of the hydrocladium agrees perfectly with that of P. multiramosa. 



No other so strongly branched species of Plumularia has been re- 

 ported from the Eastern Pacific. P. corrugata may be slightly branched, 

 and in many respects it resembles this species, but it is a much more 

 slender, and generally more delicate species than this. P. adjecta may be 

 branched also but the same statement applies. 



