vol. i.i Torrey. — Hydroida of the Pacific Coast. 7~> 



Halicornaria producta (Bale). 



PI. X. Fig. 95. 



Azygloplon produclum, Bale, Linn. Soe. N. S. W., 1888, (2), III, Pt. I, 



" p. 774. 

 Kircheupaneria producta, Bale, Proe. Koy. Soc. Viet, VI, p. 111. 



Trophosome. Colony with simple stem, divided obliquely into internodes 

 which vary in length according to age; those on the same stem are equal. 

 Hydrocladia alternate, each from a shoulder projecting from the middle 

 region of each internode. Each hydrocladium divided more or less obliquely 

 into equal hydrothecate internodes. Hydrothecae somewhat compressed, 

 with a broadly oval, smooth orifice which may be roughened by wear; about 

 as deep as long; free for one third its length. Strong intrathecal septum 

 about two-thirds the length of the hydrotheca from bottom, and reaching 

 about one-third across theca at widest point. 



No cauline nematophores. Mesial thecate nematophore very short, not 

 reaching the base of the theca, expanding into the form of a sickle-shaped seg- 

 ment of a saucer, with a diameter two-thirds that of theca and embracing the 

 internode for half its circumference. Pair of supracalycine nematophores, 

 seldom reaching higher than two-thirds the height of the theca, never reach 

 ing the rim. 



Height of longest stem 10 mm. Hydrothecae .2 mm. broad and long. 

 Internodes of stem .3 to .4 mm. in length, in breadth varying from .2 in 

 older to .12 mm. in younger colonies. Internodes of pinnae about the same 

 length, but somewhat slenderer than younger stems. 



(loiiosiutiv absent. 



Distribution. San Diego, Cal., along shore of Ballast Point; 

 growing on seaweed. Australia (Bale.) 



The trophosome agrees so well with Bale's description that I 

 do not hesitate to indentify my material with his speeies, even 

 though the gonosome is lacking. 



Plumularia. 



Trophosome. Coenosarc of stem not canaliculated. hydrocladia unbranched, 

 pinnately disposed, alternate or opposite. Hydrothecae with smooth 

 margins; all nematophores movable. 



Gonosome. Gonotheeae borne on hydrocaulus or hydrocladia, without 

 corbulae or protective structures of any kind. (Nutting's definition, slightly 

 modified.) 



Plumularia alicia, sp. now 



Pl.X. Figs. 96, 97. 



Trophosome. The colony is composed of a cluster of slender, loosely 

 branching stems rising from a creeping hydrorhiza to a height of three to 

 five inches. Each stem is divided transversely by inconspicuous nodes into 

 short internodes of equal length. Hydrocladia are borne alternately on either 



