52 Mr. H. J. Carter on Specimens 



Obs. This species is characterized by its brilliant snow- 

 white colour, the large size of its stellates, and the peculiar 

 capitation of their rays. 



Hymedesmia trigonostellata, n. sp. 

 (PI. IV. fig. U,a-d). 



Laminiform, extremely thin, spreading, smooth or hirsute. 

 Colour snow-white, glistening. Spicules of three forms, 

 viz.: — 1, acuate, long, thin, smooth, 50 by \-\ 800th 

 (PI. IV. fig. 14, a) ; 2, pin-like, ensiform, smooth, with inflated 

 fusiform shaft, long neck, and small round head not more than 

 one third of the diameter of the shaft, 25 by 1-1 800th 

 (fig. 14, b) ; 3, stellate, quadriradiate, in which three of the 

 rays form a kind of tripod to the fourth, that is erect, thus 

 presenting a triangular appearance ; each ray expanded at 

 the extremity by a multifid spinous division, 3-6000ths in 

 diameter (fig. 14, c, d). No. 1, sparsely scattered, projects 

 beyond no. 2, which is parquetted in among no. 3 in great 

 abundance, so as to present a smooth glistening surface. 

 Size variable ; that of specimen about £ inch in horizontal 

 diameter. 



Sab. Marine. On hard objects. 



Loc. Gulf of Manaar. 



Obs. The peculiar sword-like form of the pin-like spicule 

 no. 2, together with that of the stellate, characterizes this 

 species unmistakably; while the latter, which always resem- 

 bles that of Axos Clrftoni in the multifid spine-like division of 

 the extremities of its rays, is often rendered still more like it 

 by being sexradiate. 



Suberitida. 



Suberites vestigium, n. sp. (PI. V. fig. 21.) 



Laminiform, extremely thin, spreading. Colour glistening 

 white, asbestus-like. Spicule of one form only, viz. pin-like, 

 shaft slightly curved and slightly fusiform, head spherical, 

 a little less than the shaft in diameter, 27 by l-1800th 

 (PI. V. fig. 21). Spicules confusedly arranged, among which 

 many project irregularly. Size variable, that of the speci- 

 men about £ inch in horizontal diameter. 



Hob. Marine, on hard objects. 



Loc. Gulf of Manaar. 



Obs. This species, although very like a Hymedesmia in 

 growth and appearance, is also very different in spiculation. 

 As may have been observed, there is no long setaceous spicule 

 here markedly projecting from a layer of smaller ones of a 



