fiponges from the Athintlc Ocean. 229 



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

 irhcn /iriiif/, and irast ot" all wlioii allowed to dry or pass 

 into dissolution, which it does almost innnediately after death. 

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

 two in spirit broken down in strneturc, are, as just stated, not 

 in a favourable state for description. Were a fi;;ure to be 

 given of this sj)on,i;e, it would be hardly more than a blot of 

 red or crimson ink upon a piece of paper. 



Corticittm para.siticuni, 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 stmcture 

 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, especiallv towards 

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

 diameter than the thickest ])art of the shaft ; shaft conical 

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

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

 fusedly — that is, apparently without definite arrangement. 



Hal). Marine, incrusting dead stems of Esperia cujiressus 

 n. sp., var. hikamatifera. 



Loc. Station 42 = 8()2 fathoms, "chops" of English Chamiel. 

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

 Esjjeria mentioned, dredged up very near the station from 

 ■which Corticium ah^ssiMns obtained (^\nnals,' 1873, vol. xii. 

 p. 18, pi. i. fig. 1 &c.). It appears to me to be the sponge 

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

 Cometella graciUor^ whatever the original form of Cometella 

 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 theii characteristic spicules. I have often seen a parasitic 

 sponge charged with pin-like sj)icules, although not of the same 

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

 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. 



Aplysiua mpvns^ n. sp. (PI. XII. figs. 2 & 1, c.) 



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

 Ann, di' Mag. S. ffisf. Scr. 4. Vol. .xviii. l(j 



