176 BRITISH SPONGIADiE. 



pose the following series of characters to replace 

 those in Vol. II, p. 350, ' Monograph of the British 

 Spongiadas.' 



" Sponge massive, sessile. Surface slightly uneven, 

 minutely hispid. Oscula simple, dispersed. Pores 

 dispersed. Dermal membrane abundantly spiculous ; 

 tension spicula sub-fusiEormi acuate, more or less 

 constricted near the basal end, long and slender, very 

 numerous, irregular, felted together; and tricurvate 

 acerate, small and very slender, few in number ; 

 retentive spicula simple and contort bihamate, rather 

 ■small, very numerous ; and bidentate inequi-anchorate 

 and dentato-palmato inequi-anchorate, very minute 

 and few in number. Skeleton — rete open; fibre 

 stout and compact ; spicula subf usiformi-acuate, more 

 or less constricted near the base, long and large. In- 

 terstitial membranes abundantly spiculous ; tension 

 spicula same size and form as those of the dermal 

 membrane, dispersed or subfasciculated ; retentive 

 spicula same as those of the dermis. 



" Colour. — In the live state pale brown. 



" EaUtaL— Shetland, Mr. C. W. Peach; "Westport 

 Bay, Co. Mayo, Rev. A. M. Norman. 



"Examined. — In the dried state." 



5. Desmacidon incognitos, Boiv., iii, 292, PI. LXXXV, 

 figs. 14 — 16. 



•6. Desmacidon pannosus. Bow., hi, 312, PI. LXXXIX, 

 figs. 1, 2. 



*' When I described and figured this sponge it was 



