152 BRITISH SPONQIAD^. 



find it in deep water in the neighbourhood of our own 

 coasts, as we frequently meet with the deep-water 

 species near the Orkneys and Shetland. 



63. IsoDicTYA Hyndmani, Bow. 



1866 Halichondria Hyndmcmi. ll, 264; ill, 115, pi. xlvi, 



figs. 7—15. 



1867 Alehion Hyiidmcmi, Gray. Proo. Zool. Soc, p. 534. 

 1874 Isodictya Hyndmani, in, 358. 



" Among the specimens of British sponges in spirit 

 received from the Eev. A. M. Norman there were 

 some portions of the roots of fuci with thin incrus- 

 ting sponges upon them. On one of these was a thin 

 layer of I. Hyndmani labelled 'Yellow, Roundstone 

 Bay.' The usual locality of this species is on Peden 

 opercularis, and this is the second case of my having 

 found it incrusting either fuci or zoophytes. Although 

 but in a very young condition its structural characters 

 were very strongly produced, and the bipocellated and 

 unipocellated retentive spicula were more numerous 

 than is usually the case." 



64. Isodictya lueida, Bow., ii, 336; iii, PI. LVIII, 



figs. 27—32 ; PI. LXXXII, fig. 1. 



" Among the sponges received from the Rev. A. M. 

 Norman was a small, massive specimen of this species, 

 an inch and a quarter in length ; it was dredged in 

 thirty-five fathoms ofE the Durham coast. The sponge 

 was in the dried state, and in excellent condition for 

 microscopical examination, and in some thin slices at 

 right angles to the dermal surface I found in some 



