PLATE LXXVI. 229 



Oscula simple, minute, dispersed. Pores incon- 

 spicuous ; congregated in irregular areas. Dermal 

 membrane spiculous ; defensive spicula of the porous 

 areas sub-fusiformi, attenuato-acuate, basally incipiently 

 spinous, few in number : tension spicula tricurvate 

 cylindrical, slender, few in number ; retentive spicula 

 bidentate equiancliorate, very minute, few in number. 

 Skeleton dense and regular ; primary lines ; spicula 

 subfusiformi, attenuato-acuate ; occasionally subflecto- 

 acuate, large, long, and rather few in numbei- ; second- 

 ary lines very numerous, one spicalum in width ; 

 spicula incqui-cylindrical, short and stout, incipiently 

 spinous, terminations slightly inflated. Interstitial 

 membranes, retentive spicula same as those of the 

 dermal membrane, very few in number. 



Colour. — In spirit, very dark brown. 



Habitat. — Strangford Lough, Ireland ; Rev. A. M. 

 Norman, 1869. 



Examined. — Preserved in spirit. 



The specimen very closely resembles a fragment of 

 the upper leather of an old shoe, both in colour and 

 appearance. It is one inch in length, seven lines at 

 its greatest width, and does not exceed one and a half 

 line in thickness. The hispidation of the surface is 

 not visible to the unassisted eye, but it is strikingly 

 apparent in a section at right angles to the surface 

 when mounted in Canada balsam, and the oscula require 

 a two-inch lens to render them distinctly to the eye. 

 In a thin slice from the dermal surface the porous 

 areas and the pores when mounted in Canada balsam 

 and viewed with a power of about 100 linear are very 

 characteristic objects amidst the bristling field of 

 spicula surrounding them ; each area contains two or 

 three rather large pores, and the defensive spicula of 

 the areas are projected fi-'om their margins into their 

 clear spaces, at intervals. The retentive spicula are 

 best seen in situ in the porous areas ; the cylindrical 

 tricurvate ones require a power of about 100 linear to 

 render them distinctly visible, but the bidentate equi- 



