sponges from the Atlantic Ocean. 229 



while living, less so after having been placed in spirit andjwater 

 when living, and least of all when allowed to dry or pass 

 into dissolution, which it does almost immediately after death. 

 My specimens,, therefore, being for the most part dry, and the 

 two in spirit broken down in structure, ai'e, as just stated, not 

 in a favourable state for description. Were a figure to be 

 given of this sponge, it would be hardly more than a blot of 

 red or crimson ink upon a piece of papea*. 



Gorticium parasiticum, n. sp. (PI. XVI. fig. 52.) 



General form incrusting, minute, soft, fibreless. Colour 

 grey. Surface even, pierced by the ends of the spicules of 

 the species. Pores and vents not seen. Internal structure 

 composed of areolar sarcode charged with small spicules. 

 Spicules of one kind only, viz. pin-like, nearly straight, or 

 more or less curved irregularly and suddenly, especially towards 

 the large end ; head smooth, globular, a little wider in 

 diameter than the thickest part of the shaft ; shaft conical 

 not fusiform, round, sharp-pointed, microspined throughout • 

 30-40- by ^-6000ths inch, densely charging the sarcode con- 

 fusedly — that is, apparently without definite arrangement. 



Hah. Marine, incrusting dead stems of Esperia cupressus 

 n. sp., var. hihamatifera. 



hoc. Station 42 = 862 fathoms, "chops" of English Charmel. 

 Ohs. This species covers the stems of two specimens of the 

 Esperia mentioned, dredged up very near the station from 

 which Corticium abgssiv/RS obtained ('Annals,' 1873, vol. xii. 

 p. 18, pi. i. fig. l&c). It appears to me to be tlie spono-e 

 which has given the characteristic surface-spicule to Sclimidt's 

 Cometella gracilior, whatever the original form of Gometella 

 on which it grew might have been (Atlantisch. Spongienf. 

 p. 49, Taf. iv. fig. 9). There is no doubt of its being a para- 

 site here; for not only the stem, but a part of the pinnatifid 

 branches of the Esperia are present under it, together with 

 all their characteristic spicules. I have often seen a parasitic 

 sponge charged with pin-like spicules, although not of the same 

 form as that above mentioned ; and it has also often stmck 

 me that the spiculous suborder of Carnosa, viz. Gumminida 

 may by-and-by be found to pass into the suborder Suberitida 

 of my Holorhaphidota, where there appears to be no fibre 

 and no definite arrangement of the spicules, with which the 

 sarcode is densely charged. 



Aplysina ncevus, n. sp. (PI. XII. figs. 2 & 1, c.) 



General form spiniferous, flat, thin, spreading, sessile. Colour 

 Ann. & Mag. N. Bist. Ser. 4. FoZ. xviii. 16 



