Sponges from the Atlantic Ocean. 217 



becomes club-shaped at maturity, and the echinating processes 

 overrun and united together by the dermal sarcode into broken 

 ridges or rows (fig. 16, A), the surface being formed of a layer 

 of myriads of the little inequianchorates and forceps-like tri- 

 curvates (fig. 16,/), through which the ends of the skeleton- 

 spicules project, especially towards the ends of the echinating 

 processes — the peculiar form of the inequianchorate, which 

 here and there is in groups like the well-known rosettes of 

 Esperia ivgagropila &c., and the minute little spicule with 

 bulbous ends which so much resembles a pair of forceps, and 

 must be regarded as a tricurvate, all, together with the single 

 and characteristic form of the skeletoa-spicule, point out the 

 alliance of this sponge with Esperia^ while the echinating pro- 

 cesses in form and composition are very muck like those of 

 Cladorhiza abyssicola^ which will be found to be another 

 Esperian sponge. The Esperiadae come into my 5th division, 

 viz. Rayneri^. 



Chondrocladia eirgata,Wyv. Thomson. PI. XIV, figs. 20&21, 

 and PL XV. fig. 38, 



General form a tall, narrow stem, branching scantily and 

 dichotomously, rendered more or less angular by the projection 

 of conical processes arranged alternately round it in a confused 

 spiral manner ; each process inflated or jointed in the centre, 

 and surmounted by an attenuated spine-like termination, equal 

 in length to and of the same structure as the conical process. 

 Conical processes and their attenuated spine-like portions di- 

 minishing in length towards the ends of the branches, whose 

 stems, thus becoming finally divested of them, present a rounded, 

 naked, Espet-ia-like appearance. Fixed by a spreading root. 

 Colour greenish grey. Surface even, reticulate, composed of 

 dermal sarcode, charged with the flesh-spicules of the species, 

 and pierced by the pointed ends of small linear skeleton-spicules. 

 Pores and vents not seen ; probably the former are situated, as 

 usual, in the interstices of the reticular surface of the dermis, 

 and the vents scattered here and there. Internal structure, 

 composed of an axis foi-med of long skeleton-spicules, aiTanged 

 parallelly and perpendicularly together, from which radiate 

 transversely bundles of the same kind of spicules to form the 

 " conical processes " &c., imbedded in a parenchymatous sar- 

 code charged with the flesh-spicules of the species, together 

 with the smaller skeleton ones, which project through the sur- 

 face. Axis and its spicules diminishing in size upwards from 

 the base, where it forms, with the exception of a thin cortical 

 portion, the whole of the stem, intermixed with parenchymatous 



Ann. d' Ma(). N. Hist. Scr. 4. Vol. xiv. 15 



