198 



PORIFHRA. II. 



As far as I know, the following Zotrochota-spedes have hitherto been described : 



Forcepia Cart. 



The exterior varying, as a thick incrustation or thicker and more massive, or erect and formed 

 as a thick, more or less irregular leaf. The skeleton a mostly polyspicular reticulation, in the incrusting 

 or massive forms quite irregular, in the erect ones more differentiated with more or less distinct primary 

 longitudinal fibres, between which transverse spicules most frequently single, irregularly placed. The 

 dermal skeleton consisting of erect or recumbent bundles of dermal spicules, sometimes, moreover, scat- 

 tered horizontal spicules. More or less spongin present. Spicula : Megasclera ; the skeletal spicules 

 smooth or spined styli, the dermal spicules tylota. sometimes strongyla: microsclera : the characteristic 

 microsclera are spined forcipes of one or two sizes, to which a/most always are added isochelec arcuatce of 

 one or two sizes and often sigmafa. 



1. F. forcipis How. 

 PL XIX, Fig. 2 a— h. 



1866. Haliciwndria forcipis Bowerbank, Mon. Brit. Spong. II, 244, 11. 



1874. — Boverbank, ibid, III, 105, PI. XLIII, figs. 7 — 13. 



1874. — Carter, Ann. Mag. Nat. Hist. Ser. 4, XIV, 246, PL XIV, figs. 29—32, PI. XV, 



fig. 41 a — b. 

 1880. Myxilla forcipis Vosmaer, Notes from the Leyden Mns. II, 127, 12. 



') Dendy has established for it the genus Amphiaslretta. 



