282 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 4 



Plumularia margaretta (Nutting) 

 Monotheca margaretta Nutting, Amer. Hyd., I, 1900, p. 72. 

 Plumularia margaretta Fraser, Hancock Hyd., 1, 1938, p. 66. 



Fraser, ibid., 3, 1938, p. 136. 

 Fraser, Atlantic Hyd., 1944, p. 348. 

 Distribution. — 3 miles off Seal Beach, Calif., 1 1 fathoms. 



Plumularia megalocephala Allman 

 Plumularia megalocephala Allman, Gulf Stream Hyd., 1877, p. 31. 



Fraser, Hyd. Pacific Coast, 1937, p. 190. 

 Distribution. — 3 miles north of Anacapa Island, 47-52 fathoms; off 

 San Nicolas Island, 104 fathoms. 



Plumularia meganema, new species 

 Plate 39, Fig. 47 



Trophosome. — Colonies, up to 6 cm, grow from a stolon that forms 

 an irregular reticulum in a mass of sponge; they may grow quite closely 

 together but can scarcely be said to be clustered. The stem is of medium 

 thickness, but short, relatively, to the hydrocladia, divided into regular 

 internodes by quite well marked nodes. The slender hydrocladia are given 

 off alternately in the same plane, 1 to each internode near its distal end. 

 The first internode in each is short, athecate ; the second is relatively long, 

 thecate, with the small hydrotheca slightly nearer the distal end ; the third 

 internode is not quite so long as the second ; then the thecate and athecate 

 internodes appear in regular alternation ; the whole hydrocladium being 

 as much as 6 mm long. The internodal septa, 1 near each end of each in- 

 ternode, are well marked. The nematophores, and particularly the supra- 

 calycine, are characterized by their large size, or more particularly, their 

 great length; the supracalycine nematophore is as much as 0.25 mm long. 

 There is no nematophore on the short, proximal internode, but there is 1 

 mesial on each of the others. Of the cauline nematophores, there is a pair 

 in or at the axil of each process and 1 lateral on each internode, on the 

 side opposite the process. 



Gonosome. — Not observed. 



Distribution. — Station 650-37, east of San Francisco Island, Gulf of 

 California, 47 fathoms; northeast of Anacapa Island, 45 fathoms; 3}^ 

 miles south of Hueneme, Calif., 29-30 fathoms; Rosario Bay, Lower 

 Calif., 15 fathoms; east of San Marcos Island, Gulf of California, 18 

 fathoms; Puerto Refugio, Angel de la Guardia Island, 50-75 fathoms; 

 off Magdalena Island, Tres Marias Islands, Mexico, 13 fathoms. 



