200 A MONOGEAPH OS THE 



fasciculi, but the latter are always in a dispersed con- 

 dition. 



I subsequently received a second specimen of this sponge 

 from Captain Thomas, from the same locality. He describes 

 it as " about four inches over, and three or four lines thick ; 

 the colour was pure vermilion, the surface smooth and 

 shining, apparently without oscula, the substance firm and 

 fleshy on fracture. The general appearance of the sponge 

 when fresh is like a piece of fowl's liver." 



29. Htmeniaoidon subebea, Bowerbanh. 



Spongia stibekia, Montagu. 

 Halichondria suberica Fleming. 

 — SUBEBEA, Johnston. 



Sponge. Sessile, coating, or massive ; compact and fleshy. 

 Surface smooth and even, with terminations of spicula 

 occasionally projecting through it. Oscula in young 

 specimens often inconspicuous ; in mature ones largej 

 simple, and few in number. Pores inconspicuons. 

 Dermal membrane pellucid, aspiculous. Skeleton : 

 spicula fusiformi-spinulate, variable in size and tenuity ; 

 gathered more or less into expanding fasciculi as they 

 approach the surface. 



Colour. — Alive, yellow or orange ; dried, yellow or 

 brown. 



Locality. — The whole of the British coasts. 

 Examined. — In the living and dried state. 



A careful examination is required to distinguish accu- 

 rately between this species and H. carnosa. In large 

 massive specimens, or when coating shells, it may usually 

 be safely conchided that the sponge will prove to be li. 

 suberea, but when it happens to have been based on a Denta- 

 lium,a Vermetus,or some other equally ill- chosen locality, not 

 affording it surface for basal expansion, it frequently assumes 

 very much the pedestalled lobular form of H. carnosa. 

 Nor does a microscopical examination immediately solve 



