NO. 1171. HYDROIDA FROM ALASKA AND P UGET SO UND— NUTTING. 7 45 



alternate arrangement; branches and branchlets composed of unusually 

 long iuternodes, each of which gives off a hydrophore at its distal end 

 and shows two or three decided annulations at its proximal end, the 

 annulations on the distal part of the branches being decidedly oblique. 

 The iuternodes on the ultimate branchlets are arranged so as to give a 

 decidedly zigzag appearance, although this largely disappears as we 

 approach the larger branches and main stem. 



Hydrothecte occur either singly or in pairs at the distal end of each 

 internode; their pedicels are sometimes annulated proximally, but free 

 from annulations on the distal parts of the branches; margins usually 

 moderately everted, but sometimes greatly so, as in H. beani; . the char- 

 acteristic circlet of bright dots is very strongly marked. Hydiauths 

 large, bodies thick, ovate; tentacles sixteen to twenty. 



Gonosome. — Gonangia borne singly in the axils of the branches and 

 branchlets, regularly ovoid in one view, barnacle-shaped in the other; 

 aperture large, terminal. The appearance of the contents of some of 

 them would indicate the possible presence of an acrocyst at a later 

 stage of development. 



Locality. — Puget Sound. Collected by the Young Naturalists' Soci- 

 ety in the summer of 1895. 



This species is most closely allied to H. labrosum Alder, from which 

 it differs in the limited amount of fasciculation of the hydrocaulus, in 

 the much longer iuternodes of the stem, in the comparatively slight 

 amount of annulations throughout, and in the i^osition of the gonangia, 

 which are axillary in H. (jeniciilatum, while they are borne in rows on 

 the branches of H. labrosum. 



The stems in the s])ecimens secured are so invested with parasitic 

 growths that they appear much more compound than they really are. 

 In fact, the fasciculation is very limited and in some specimens not 

 apparent. The specimen also resembles H. aracile^ Bale,'' which is, 

 however, monosiphonic, and, judging from the figure, not distinctly 

 geniculate. 



HALECIUM CORRUGATUM, new species. 

 (Plate LXIII, tigs. 2 J, B.) 



Trophosome. — Hydrocaulus springing from a creeping root stalk, 

 stem simple, not fascicled, and seldom branched, the branching when 

 present having no regularity whatever. Ordinarily the hydiocalus 

 consists of single pedicels supporting hydrothecjie and resembling in 

 manner of growth the simple unbranched campauularians. Pedicels 

 closely and very distinctly annulated or corrugated throughout. Hy- 

 drothecte small, with everted margins and the characteristic necklace 



'The name Haledum ^-rad/e is preoccupied, having been used by Verrill in 1874. 

 Invertebrate Animals of Vineyard Sound, 1874, p. 328. 



2 On Some New and Rare Hydroida in the Australian Museum Collection, Proc. 

 Linu. Soc, New- South Wales, 1888, p. 759. 



