370 A MONOGRAPH OF THE 



4. Chalina Flemingii, Bowerbanh. 



Sponge. Sessile, irregularly latticed by cylindrical inos- 

 culating tubular branches. Surface smooth. Oscula 

 slightly elevated or terminal, large. Pores incon- 

 spicuous. Dermis furnished with a stout kerato- 

 fibrous reticulation, with a uniserial line of acerate 

 spicula more or less variable in size. Dermal mem- 

 brane pellucid, thin, sparingly spiculous ; spicula same 

 as those of the dermal reticulation and of the skeleton. 

 Skeleton rather open and diffuse ; fibres stout, primary 

 and secondary lines, spicula uniserial; interstitial 

 spaces frequently the width of the length of two or 

 three spicula. Spicula acerate very slender. Inter- 

 stitial membranes nearly obsolete, rarely spiculous; 

 tension spicula few in number, same as those of the 

 skeleton. 



Colour. — Dried, light brown. 



Habitat. — Brighton, Mr. Thomas Ingall. 



Examined. — In the dried state. 



I have seen but one specimen of this species, it was 

 given to me by my late friend Mr. Thos. Ingall, among a 

 number of specimens of C. Montaguii, which it very closely 

 resembles in form and general appearance. It is softer and 

 more flexible to the touch, and the branches are more 

 decidedly tubular than those of that species. In size it 

 does not extend more than an inch and a half in any direc- 

 tion, and it is parasitical on a small Fucus, in company 

 with two small specimens of Halichondria panicea. 



The kerato-reticular dermal network is stout and well 

 produced; the spicula are of the same proportions as 

 those of the skeleton, acerate, and very slender. A very 

 few fragments of the dermal membrane remained in situ, 

 and in these a few spicula of the same form and propor- 



