112 BRITISH SPONGIAD^. 



35. Halichondkia nigeioans, Boiv., ii, 2G6; in, PI. 



XLV, figs. 25—31. 



1867 lophon nigricans. Gray. Proc. Zool. Soc, p. 534. 



36. Halichondkia albula, Bow., ti, 268; iii, PI. XLV, 



figs. 21—24 



1867 Dendoryx albula. Gray. Proc. Zool. Soc, p. 536. 



37. Halichondeia expansa, Bow., in, 212, PI. LXXIV,. 



figs. 7—12. 



1869 Halichondria expansa, Bowerbank. Norman, Notes on 

 a few Hebridean Sponges, Ann. Nat. Hist., ser. 4, 

 vol. iii, p. 298. 



88. Halichondeia viegea. Bow., n. sp., iv, PI. V, 

 figs. 1—7. 



1875 Halichond/ria virgea, Bowerbank. Report Dredging off 

 the Durham and N. Yorkshire Coasts, Brit. Assoc. 

 Rep., 1875 (1876), p. 198. 



" Sponge massive, sessile, more or less nodulous. 

 Surface smootH. Oscula simple, dispersed. Pores in- 

 conspicuous. Dermal membrane abundantly spiculous, 

 tension spicula acuate, very long and slender, nume- 

 rous, fasciculated; retentive spicula bidentate, equi- 

 anchorate, large, few in number, and the same form, 

 small and numerous. Skeleton — rete more or less 

 regular, fibres rarely multispiculous, seldom more than 

 trispiculous ; areas large ; spicula subfusiformi acuate, 

 basally spinous. Interstitial membranes spiculous ; 

 spicula same as those of the dermis ; tension spicula 

 of rare occurrence ; retentive spicula rather numerous. 



