GENUS SALPINGCECA. 



351 



The shape of the lorica, apart from the salt-water habitat, of this type, at once 

 suffices to distinguish it from Salpingoeca gracilis, which it in some respects sHghtly 

 resembles. The investing sheath has never as yet been found perfectly straight as 

 in that species, but always has one or more graceful curvatures; this, combined 

 with its evenly increasing diameter, communicates to this structure a contour closely 

 resembling the graceful curving horns of certain antelopes, and has suggested the 

 specific title given. 



Upon one occasion. Fig. n, a lorica was found having a bifurcation at its 

 distal extremity, each of the separate tubular terminations being occupied by a 

 single zooid. Whether this example was the product through fission of a single 

 primary individual, or was derived through the attachment of an independent 

 gemmule to a half-formed lorica, could not at the time be satisfactorily ascertained ; 

 the former alternative would, however, appear most probable. The animalcules of 

 Salpiiigceca corniita, while frequently presenting the subcylindrical shape most 

 characteristic of S. gracilis, is subject, through the great plasticity of its substance, 

 to a very extensive range of variation. Not unfrequently it assumes that soda-water- 

 bottle or clavate shape, with an attenuate anterior extremity, characteristic of various 

 other members of the same generic group, while on other occasions again (Fig. 35) 

 it has been observed with these proportions exactly reversed, the posterior end 

 being the narrower one of the two, and the characteristic collar and flagellum being 

 developed from the larger one. Examples of this species were first obtained growing 

 on Polyzoa and hydroid zoophytes gathered at Bognor, Sussex, in September 1872, 

 as also more recently (October 1875) from the tanks of the Manchester Aquarium. 



Salpingoeca tuba, S. K, Pl. VI. Fig. 38. 



Lorica sessile, subcylindrical, rounded posteriorly, slightly constricted 

 anteriorly, the frontal margin somewhat everted; enclosed animalcules mostly 

 flask-shaped, with a rounded and inflated posterior and narrower neck-like 

 anterior region, occupying one-half or the greater portion of the cavity of 

 the lorica ; sometimes subcylindrical and attached by their posterior extre- 

 mities to the bottom of this structure ; collar largely developed, equalling 

 the body in height. Length of bodies 1-4000" to 1-2000". 



Hab. — Salt water, social. 



This species was obtained by the author in September 1879, attached in social 

 clusters to zoophytes and marine ConfervcB collected at St. Heliers, Jersey. But for 

 its smaller size and salt-water habitat it might have been identified with the sessile 

 variety of Salpingceca gracilis represented at PI. VI. Fig. 32. Additional points may, 

 however, be cited that seem to indicate its distinctness from that form. The con- 

 tained animalcules always occupy at least one-half of the cavity of their respective 

 loricae, and not uncommonly its entire length, being under such conditions 

 attached by their posterior extremities to the bottom of their domiciles, as indicated 

 in the example to the extreme left in the group shown at Fig. 38. When freely 

 suspended within their lories they almost invariably assume an attenuate flask- 

 shaped contour, corresponding closely with that frequently exhibited by Salpingceca 

 corniita, but never presented by 5. gracilis. 



Salpingoeca gracilis, J.-Clk. Pl. VI. Figs. 25-32. 

 Lorica elongate, vaginate or subcylindrical, straight, five or six times 

 as long as broad, sometimes rounded, in other instances more or less 

 attenuate or even pedunculate posteriorly, the anterior margin slightly 

 everted, somewhat constricted beneath this region ; contained animalcule 

 subcylindrical elongate, occupying from one-fourth to one-third of the total 



