Sponges from the Atlantic Ocean. 249 



without any bend), and even longer than the skeleton-spicule 

 of the species ; while throughout it was enclosed by a delicate 

 nucleated mother-cell, shaped like a bolster. 



The mounted specimen of Suberites arciger which Schmidt 

 sent to the British Museum, besides the tricurvate, presents 

 the true pin-like skeleton-spicule of a Suberite. 



In Halichondria forcipis both the skeleton-spicules and 

 equianchorates are very much allied, in general form, to those 

 of Halichondria incrustans ; but in place of the bihamate 

 of the latter we have the fore ipi form tricurvate in the former, 

 while the " crumb-of-bread "-like appearance of the structure, 

 in the general form, is very much like that of Halichondria 

 incrustans, which used to be designated " H.jpanicea." 



Cliona abyssorum, n. sp. PI. XIV. fig. 33, and 

 PI. XV. fig. 45, «, b, c. 



Sponge retiform, permeating the branches of LophoheTia 

 prolifera, and appearing here and there in small heads through 

 corresponding holes in this coral. Pores and vents respec- 

 tively in these heads. Internal structure areolar, charged 

 with the spicules of the species, and permeated by the excre- 

 tory system, which is more areolar than tubular. Spicules of 

 two kinds, viz. skeleton- and flesh-spicules. Skeleton-spicules 

 of two forms, viz. : — 1st, the largest, smooth, pin-like, fusiform, 

 curved, fine-pointed, chiefly confined to the " heads," average 

 largest size 57 by f-1800th inch in its greatest diameters, 

 head oval and as wide as the shaft (PI. XV. fig. 45, a) ; 2nd, 

 the small skeleton-spicule, smooth, curved, fusiform, acerate, 

 fine-pointed, chiefly confined to the body, average largest size 

 25 by f -1800th inch in its greatest diameters (fig. 45, b). 

 Flesh-spicule of one form only (fig. 45, c), smooth, spiral, 

 sinuous, straight, abruptly terminated at each end, and pre- 

 senting four bends on each side in its course, densely charging 

 the sarcode throughout ; average largest size 20 by 1 -6000th 

 inch in its greatest diameters. Size of entire specimen unde- 

 finable from its fungus-like permeating growth. 



Hob. Deep sea, permeating the branches of Lophohelia 

 proliferai 



Loc. Atlantic Ocean, " chops " of English Channel. 



Obs. The specimen of Lophohelia prolifera in which this 

 sponge was found is partly enveloped in Corticium abyssi, 

 which having already been figured and described in the 

 1 Annals ' of 1873 (vol. xii. p. 17, pi. i. figs. 1 & 2), I must 

 refer the reader to that for all particulars concerning this part 

 of its history, merely observing that it was dredged up from a 



