2 Mr. H. J. Carter o/i two neio Calcispongiae. 



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

 2, «), 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 tlie sm-facc generally. Internal structure 

 close, areolar, accompanied by the branching excretor}' canal- 

 system. Spicules of one form only (fig. 4), viz. Hnear, 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 l-12th of an inch high. 



Hah. Marine. Laminarian zone, in company with Isodictya 

 simularis, Bk. [Halichondria simulanSj 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 egg, to- 

 gether with branching and inosculating Isodictya simulanSj 

 the whole of which had probably become entangled in the 

 Laminarian zone, whence it had been torn ofi" 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 Leuconia nivea 

 that the vent branches oft" directly into the areolar parenchvma 

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

 and smooth, is rather elevated and i-ough, or iiTCgularly ridged, 

 while the whole mass has the appearance of the pile on 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 sav ; but it is 

 chiefly caused by the pnijection of tlie attenuated sjiinous ends 

 of the sinuously straight spicules, wliicli, 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, gj^psum, t!cc. 



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

 linear, this Calcis])onge further diftei-s from all the others with 

 which I am ac(puiintod in ])ossessing no triradiatc or quatU'i- 

 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 " Tricliogypsia^^^ designating the species by the term 



