2 Mr. H. J. Carter on two new Calcispongias. 



fig. 2), presenting a single vent at one end of the ellipse (fig. 

 2, a), about midway between the border and the centre, at the 

 bottom of an oval excavation, furnished internally with a 

 circle of minor vents arranged round the large one (fig. 3). 

 Pores scattered over the surface generally. Internal structure 

 close, areolar, accompanied by the branching excretory canal- 

 system. Spicules of one form only (fig. 4), viz. linear, sinuous, 

 fusiform, spino-tuberculate at the extremities, especially the 

 outer one, which is most attenuated, the internal one being 

 obtuse and less tuberculated ; arranged more or less perpen- 

 dicularly, so as to present a villous surface. Size of spicule 

 averaging 32-1800ths of an inch long by l-1800th of an inch 

 broad. Size of specimen (fig. 1) 5-12ths of an inch long by 

 3-12ths broad, and 1-1 2th of an inch high. 



Hah. Marine. Laminarian zone, in company with Isodictya 

 simulans, Bk. {Halichondria simulans, Johnston). 

 Loc. Budleigh-Salterton, south coast of Devon. 

 Ohs. I have only obtained one specimen of this sponge ; 

 it had grown upon the deciduous shell of a shark's o.^^^ to- 

 gether with branching and inosculating Isodictya stmulans, 

 the whole of which had probably become entangled in the 

 Laminarian zone, whence it had been torn off in a storm 

 and cast upon the beach, where I found it about a year 

 since. 



It consists of a single individual, with one vent, growing 

 flat upon the horny egg-shell, and is so far like Leucoma nivea 

 that the vent branches off" directly into the areolar parenchyma 

 of the sponge ; but its surface, instead of being depressed, flat, 

 and smooth, is rather elevated and rough, or irregularly ridged, 

 while the whole mass has the appearance of the pile oh white 

 velvet which, having been moistened with gum-water, has 

 been allowed to dry in a ruffled state. How far this may be 

 owing to the washing of the sea-water, I cannot say ; but it is 

 chiefly caused by the projection of the attenuated spinous ends 

 of the sinuously straight spicules, which, an-anged perpendi- 

 cularly to the sm-face, give the latter its villous appearance. 

 The colour is greyish or greenish white, of that tint which is 

 perhaps the most common in the crystalline salts of lime — 

 calc spar, gypsum, &c. 



While, however, there is only one kind of spicule, and that 

 linear, this Calcisponge further differs from all the others with 

 which I am acquainted in possessing wo triradiate or quadri- 

 radiate spicules. 



It is necessary to make a new genus of it, for which, from 

 its calcareous nature and hair-like appearance, I propose the 

 name of " Trichogypsia,^^ designating the species by the term 



