THE HYDROIDS l8l 



HALECIUM ORNATUM sp. nov. 

 (Plate XXII, figs. 3,4.) 



7 ropkosome. — Colony parasitic, branching irregularly. Stems not 

 fascicled, the stem and branches sparsely and irregularly annulated. 

 Pedicels long, of equal diameter throughout. Hydrophores with broad, 

 everted inargins, occasionally reduplicated. Hydranth large, with 

 twenty-four to thirty tentacles. 



Gonosome. — A single apparently young gonangium was borne on a 

 pedicel just below the hydrophore. It was in form a truncated and 

 deeply annulated cone. Probably the mature gonangium would 

 resemble that found in the next species. 



Distribution. — Berg Inlet, Glacier Bay, Alaska. Growing on 

 Lafcea gracillima (Harriman Exped.). 



HALECIUM SPECIOSUM sp. nov. 

 (Plate XXII, figs. I, 2.) 



Trophosome. — Colony small, attaining a height of about Yi inch. 

 Stem not fascicled, the main stem and branches apparently formed of 

 series of stout pedicels, each giving origin to another pedicel just below 

 the hydrophore. The pedicels thus take the place of stem joints, 

 bending alternately to the right and left, giving a geniculate appearance 

 to the series. Pedicels broad, corrugated proximally and smooth 

 distally. Hydrophores large, with broadly expanded but not everted 

 margins, and a well marked row of dots. There appears to be no re- 

 duplication of the margins. Hydranths very large with twenty-four to 

 thirty short tentacles, a broad oral disk occupied, by the low dome- 

 shaped proboscis. 



Gonosome. — Gonangia borne on rather long annulated pedicels be- 

 low the hydrophores, particularly on the upper part of the colony ; 

 regularly ovoid in outline, and evenly and beautifully annulated 

 throughout. 



Distribution. — Yakutat Bay, Alaska (Harriman Exped.). 



This is the most strikingly ornamented species of Halecium known 

 to the writer. Its manner of growth is exceptional, although not un- 

 known among its allies, and the hydranth is more like the polyp of 

 some actinozoon than of a hydroid. The gonangia are beautiful struc- 

 tures. They seemed to be filled with a granular, ovoid mass, probably 

 a single large sporosac. 



