104 AMERICAN HYDKOIDS. 



DixtrHmt!,,,,. -All.iffons Station 3180, lat. N. 52 06', long. W. 171 45', 283 fathoms. 

 Bering Sea. 



This species bears some resemblance to S. gigantea Mereschkowsky, but the hydrothecse are 

 quite different in shape. No better example could be found of the futility of basing generic 

 distinction on the number of parts to the operculum. One branch of this species could be 

 placed in three different genera were that criterion to be used. 



Type. In the collection of the U. S. National Museum. 



SERTULARELLA FORMOSA Fewkes. 

 (Plate XXVII, figs. 2-4.) 



Sertularella formosa FEWKES, Bull. Mus. Comp. Zool., VIII, No. 7. ISsl, p. 130. 



Si'iinlnriit inli -i/rilhcca ALLMAN, Challenger Report, Hydroidu, Pt. 2, 1888, p. 60. 



Sertularella formosa NUTTING, Bahama Expedition, 1895, p. 88. 



Sertnlarella integrltheca VEKSLUYS, Hydraires de 1'Hirondelle, 1899, p. 37. 



,S'i ///' i ;<//(( cylindrithfcii HARTLAUB, Revision der Sertularella-Arten, 1900, p. 77 (part). 



Trophosome. Colony attaining a height of about 6 inches. Stem not fascicled, sinuous, 

 interuodes not evident. Branches regularly alternate, there being three hydrothecffi between 

 adjacent branches on the same side, divided into regular internodes each of which bears a hydro- 

 theca. Hydrotheca 1 ! entirely exserted, cylindrical, set nearty at right angles with the stem or 

 branch, sides nearly parallel; aperture perfectly round and smooth, except for a submarginal 

 annulation or rim, which is not always present. Operculum apparently wanting. Sometimes, 

 however, it appears in the shape of a thin membrane stretched like a drumhead across the 

 aperture. 



Gonmonte. Gonangia oblong-oval, inserted on the bases of the hydrothecse, with smooth 

 walls and a truncated distal end closed with a four-flapped membranous operculum. 



Distribution. Off Granada, 170 fathoms; off Martinique, 357 fathoms (Fewkes); off Habana, 

 Cuba, abundant, 100 to 200 fathoms (Nutting); Testigos Island, 11 meters (Versluys); Albatross 

 Station 2157, lat. N. 23 10' 04", long. A^ 7 . 82 21' 07", 29 fathoms; Station 2324, lat. N. 23 

 10' 25", long. W. 82 20' 24", 33 fathoms. 



Having secured a portion of Allman's type of S. integritlieea, and compared it carefully with 

 S. furni/iK/i Fewkes, I do not hesitate to consider the two species as identical. Hartlaub 1 

 regards S. imtegritheca and S. cylindritheca Allinan as identical. Having seen both types, I am 

 unable to agree with him, and the matter is perfectly plain when the types can be consulted. 



Tujw. In the Museum of Comparative Zoology, Cambridge, Massachusetts. 



SERTULARELLA HARTLAUBI, new species. 

 (Plate XXVII, fig. 5.) 



Trophosome. Colony (fragmentary) about 2 inches high. Stem straight, dark colored, not 

 fascicled, divided into fairly regular nodes by very faintly marked oblique nodes, each internode 

 bearing a hydrotheca or a hydrotheca and a branch. Branches alternate, given off at right 

 angles to the stem from just below the bases of the hydrothecse, sharply constricted at their 

 bases. Only the stumps of branches remain in the type specimen, but another specimen from 

 a widely different locality consists apparently of detached branches, which are long and slender 

 with obscure nodes. Hydrotheca} exceedingly shallow, shaped like the base of a low, truncated 

 cone, with its axis forming nearly a right angle with that of the branch; margin perfectly 

 smooth and even; operculum in some cases an adcauline flap, in others apparently an irregularly 

 ruptured membrane stretched straight across the aperture like a drumhead. 

 Not known. 



AtlHiti^xx Station 2136, lat. N. 17 43' 40", long. W. 75 38' 25", 52 fathoms; 

 Station 2796, lat. S. 8 5', long. W. 78 51', 33 fathoms. 



'Revision der Sertularella-Arten, 1900, p. 77. 



