220 Mr. H. J. Carter on Deep-sea 



tonii a great resemblance in every way to CJiondrocladia 

 virgata. 



The single and peculiar form of the skeleton-spicule in 

 Cladorhiza and Chondrocladia^ with the anchorate and bi- 

 hamate, point to a strong alliance with Esperia, Carter, at the 

 same time that their rigid stems, composed of closely united 

 parallel spicules (in Cladorhiza anastomosing also) present 

 a strong resemblance to the characteristic fibre-skeleton of 

 Esperia. 



Histoderma appendiculatum , n. gen. et sp. PL XIY. 

 figs. 23-25 and PI. XV. fig. 39, a, h. 



General form subglobular, smooth, furnished with several 

 narrow tubular prolongations of different lengths, some of 

 which are longer than the diameter of the body (PI. XIY. 

 fig. 23). Free. Colour light grey. Composed of a stiff glisten- 

 ing bladder-like dermis (fig. 23, a), which also forms the 

 walls of the tubuli (fig. 23, ^), and encloses throughout a soft 

 fibreless parenchyma. Dermis a woven-like texture, con- 

 sisting of a dense layer of linear spicules intercrossing each 

 other on the same plane, and held together by tough horny 

 sarcode extending into the tubular prolongations, whose 

 cylindrical walls respectively are similarly constructed, and, 

 like the body, retain their form when dry and emptied of 

 their contents. Tubuli terminating abruptly, each followed 

 by a small conical eminence (fig. 23, c) which appears to 

 have had the power of opening and closing itself as required. 

 Pores and vents not distinctly seen, but probably situated at 

 the extremities of the tubuli respectively, which, with the ex- 

 ception of one instance (fig. 23, c), from Avhich the above de- 

 scription is taken, are all broken off. Internal structure 

 massive, fibreless, charged with the spicules of the species 

 and permeated by the excretory canal-systems, which appear 

 to have had their vents respectively at the ends of the tubuli. 

 Spicules of two kinds, viz. skeleton- and flesh-spiculcs. 

 Skeleton-spicules of two forms, viz. : — one, the largest, smooth, 

 slightly curved, acuate, abruptly pointed, average largest size 

 64 by l-1800tli of an inch in its greatest diameters (PI. XV. 

 fig. 39, a) ; the smaller one smooth, slightly curved, fusiform, 

 terminating at each extremity in a constricted neck, followed 

 by a remarkably large elliptical pointed inflation, average 

 largest size about 40 by ^-1 800th inch, inflated ends wider 

 than the shaft (fig. 39, Z*). Flesh-spicules also of two forraSj 

 viz. bihamate and equianchorate. Bihamate (PI. XIV. 



