48 University of California Publications. [zoology. 



hydrothecae are characteristic of both Plumulariidae and Sertu- 

 lariidae. The mode of branching, while exhibiting at times a 

 certain irregularity suggestive of the Gymnoblastea, most nearly 

 approaches the type of branching in the Campanulariidae, which 

 family the Haleciidae further resemble through such forms as 

 Diplocyathus dic.hotomous Allman, in which the hydrothecae have 

 rudimentary stalks, and Campalecium medusiferum, described 

 below, in which the gonotheca contains a series of medusoid gono- 

 phores. 



This union of the characters of the various families of the 

 Calyptoblastea is strong support for the view, which I am 

 disposed to adopt, that the Haleciidae stand nearest of them all 

 to the ancestral Gymnoblastea. 



Campalecium, gen. now 



Trophosome. As in Halecium. 



Gonosome. Gonotheeae each with a blastostyle bearing several medusoid 

 gonophores. 



This genus bears a relation to Halecium similar to that 

 between Gonothyraea and Campanularia. The distinction is not 

 a sharp one, being based on the degree of degeneration of the 

 gonophores, yet it is serviceable in the absence of intergrading 

 forms. 



Campalecium medusiferum, sp. nov. 



PI. III. Figs. 26, 27, 28, 29. 

 Halecium lenellum, Clark, Trans. Conn. Ac, 1876, III, p. 255. 



Trophosome. Stems short (5-10 mm.), sparingly and irregularly 

 branched, rooted by a creeping stolon. Hydrotheca with strongly everted 

 rim. Hydranth large, with low conical proboscis and 24 to 28 tentacles in 

 one whorl. 



Gonosome. Gonotheca on short peduncle arising just below a hydro- 

 theca; about three times as long as broad; broadest at distal end which 

 is truncate, tapering gradually to the peduncle. Orifice not determined. 

 Gonophores 2 to 5, in linear series, medusoid, with 4 tentacles developing 

 in pairs which differ in size, and a conical manubrium. 



Distribution. Long Beach, Cal., in 6 fathoms. Bottom 

 covered with Nitophyllum. July 6, 1901. 



The material consists of a few stems on a stolon which was 

 tangled round the bases of stems of P. setacea and S. halecina. 

 The skeletal characters agree closely with Hincks's description of 



