NO. 5 FRASER : HYDROIDS 283 



Plumularia micronema Fraser 

 Plumularia micronema Fraser, Hancock Hyd., 3, 1938, p. 142. 



Distribution. — Off San Pedro; Tagus Cove, Albemarle Island, Ga- 

 lapagos, 10-18 fathoms. 



Plumularia mobilis, new species 

 Plate 40, Fig. 48 



Trophosome. — The colony is small, 18 mm, growing from a linear 

 stolon. The branched stem is divided into regular internodes by well 

 marked nodes; the same is true of the branch, which is very much similar 

 to the stem in every way. The hydrocladial process is given off the distal 

 end of the internode, adjacent to the distal node. It is difficult to describe 

 the division of the hydrocladium into internodes as there seems to be no 

 fixed plan of division. The internode next to the process is always athecate, 

 but it varies much in length ; in some of the hydrocladia, the second inter- 

 node is thecate, but in others, a second, athecate internode appears before 

 the first thecate internode. Following the first thecate internode, there 

 may be 1 long, athecate internode, followed by a thecate internode, but 

 just as often there are 2 athecate internodes present here; these vary 

 much in length in different hydrocladia. The remainder of the hydrocla- 

 dium has the same type of variation as that just described. In all of the 

 internodes, there are flanking septa for each of the nodes, quite well 

 marked. There is greater consistency in the nematophores ; each thecate 

 internode bears a pair of supracalycine nematophores and a mesial nemato- 

 phore proximal to the hydrotheca; the first short, athecate internode has 

 no nematophore, but each of the others has one. On the stem and branches 

 there is a small nematophore in the axil of the hydrocladial process and 2 

 lateral nematophores on the side opposite the process. 



Gonosome. — Not observed. 



Distribution. — Station 1240-41, 9 miles off San Diego, Calif., 78-81 

 fathoms; 10^ miles west of Point Dume, 47-48 fathoms; 1 mile SW of 

 Ben Weston Point, Santa Catalina Island, 45-49 fathoms; 1^ miles 

 north of Cedros Island, 45-55 fathoms. 



Plumularia multiramosa, new species 

 Plate 40, Fig. 49 



Trophosome. — Colonies, 9 cm, are segregated ; the stem is simple but 

 stout, giving rise to numerous long branches, alternately arranged, in the 

 same plane, thus the colony is strongly flabellate; the primary branches 



