112 AMERICAN HYDROIDS. 



an internal marsupium is present in mature specimens. Male gonangia rather slender for this 

 genus, oblong conoid, with six to eight longitudinal ridges becoming more prominent distally 

 and ending in a circle of six to eight elevated points, which surround the slender tubular neck 

 which occupies the center of the distal end of the gonangium. 



I>;xtr;i,,it;,,n. An><iti-xx Station 24i:>, lat. M. 30 44', long. W. ?. I'll', 44o fathoms; Station 

 2663, lat. N. W 3!t', long. YY. ?. 4:i', 4'Jl fathoms: Station *\M, lat. X. ;>,(> 47' :io", long. W. 

 79 4!', -J7) fathoms; Station -JtJf.s, hit. X. M 5S' :-!()". long. W. 7l'-' 38' 30", a4 fathoms. 



This species seems to lie the most southerly in its distribution of all of the typical Diplmx'ni 

 species, and is also found in deeper water than is usual in this group. It is probably nearest 

 I). jtiiuiKtii, from which it differs in having a sharp constriction at the base of each branch, 

 alternate and more distant hydrotheca-. and in the character of the male gonangium. I take 

 pleasure in naming this verv beautiful form in honor of Mr. .1. H. Paarmann, who has done 

 much to elucidate the structure of the operculum in this family of hydroids. 



TyjH xl!<l,x. -Cat, No. l!7i7. I'.S.X.M. Cat. No. js7L ; <l, Museum of State University of 

 Iowa; also in collection of the author. 



DIPHASIA CORNICULATA (Murray). 



(Plate XXIX, fift. 1.) 



Si'rliiliirin rnriiiriiliiln Mi'RKAY, Ann. ami Man., 3d ser., V, 1860, p. 251. 

 I>iji/i<ixiii rnriiifiiiiitii A. AciAssi/, North American Acalepluc, isii.'i, p. ]4:i. 

 Kerliiltiriii r/iriiii-ii/iiln CLARK, Hydroids nf the Pacific Coast, ISTfi, ].. 251. 



" Cells not quite opposite, sometimes nearly alternate, forming an open cup resting on the 

 stem: lip not distinct; exterior margin somewhat projecting at tip; a single one in the axilla of 

 each pinna. Vescicles pear-shaped, with two long points projecting like horns at the thick end; 

 aperture between them." 



Distribution. "Bsij of San Francisco (Murray). 



I have not seen this species, and copy tlie above description, which is entirely inadequate, 

 from the original by Murray. His tigure. which I also copy, shows that the gonangia, or at 

 least one of them, resemble that of I>. tuiin/rixi'i/, but. the hydrothecse seem much stouter and 

 more nearlv opposite, 



DIPHASIA KINCAIDI (Nutting). 

 (Plate XXXI, lij;s. 7-!l.) 



Tliiiinriii 1'li'i/iiiin Nrrrixi;, Ilydroids <>f the Ilarriinan Isxpi-ilition, 1001, p. 1S7. 

 Thninriii kiiirniili Nl'TTixn, American Naturalist, Sept., 1901, p. 7S9. 

 Tliuinriu i'/,'i/inix TOHRKY, Hydrnicla of the Pacific Coast, l'.KI2, p. 14. 



Trophosome. Colony plumose, attaining a height of about (J inches. Stem not fascicled, 

 with a row of hydrothec-e on each side, divided by oblique nodes into long and irregular 

 internodes; in distal part, each internode bears from two to four branches. Branches irregularly 

 alternate, unbranched for about their proximal half, the distal portion dividing into a number of 

 branchlets, the whole giving a very elegant plumose appearance to the colony. Branches 

 divided into irregular internodes by oblique nodes, each internode ordinarily hearing more than 

 two hydrothecse. liydrotheca 1 subalternate, short, stout, pitcher-shaped, the abcauline outline 

 being a double curve and the adcauline a single curve; margin sinuous, like the mouth of a 

 pitcher. Operculum consisting of a large, slightly vaulted adcauline Hap. The top of one 

 hydrotheca is separated by a considerable space from the bottom of the one immediately above it. 



tin/KiftiiiiK'. Gonangia arranged in crowded double rows along the distal parts of the stem 

 and branches, small for this genus, rather slender, oblong-oval, the distal end truncated and 

 entirely occupied by the large round aperture. There is an internal distal plug which appears as 

 a dark collar in fresh specimens. The gonangia have no spines or external projections of any 

 sort. 



Distribution. Berg Inlet and Dutch Harbor, Alaska (Nutting). Collected bv the Ilarriman 

 Alaska Expedition. 



TI/JX- xlnl.x. -Cat. Nos. L!t7H;">, l'.7'.tf,. I'.S.N.M. Cat. No. ls7i'.">. Museum of State University 

 of Iowa; also in the collection of the author. 



