Knowledge of the Spongida. 353 



diameter (fig. 4, c and e) ; 2, minute stellate, about 2-6000ths 

 inch in diameter (fig. 4, d and f). Incrustation, which is 

 strikingly reticulated, comparatively thick, t. e. about l-96tli 

 inch in vertical diameter (fig. 4, #, h). Size of entire speci- 

 men 3 inches high and 2 inches in horizontal diameter. 



Hab. Marine. 



Loc. ? 



Obs. As the large globostellate when fully developed ap- 

 pears to stop at the form and diameter above mentioned, but 

 may be found of all sizes below this, so the former appears to 

 be its normal condition, which is almost identical, as before 

 noticed, with the abnormal one of the siliceous body or ball 

 in Geodia canaliculata. The characteristic reticulation of the 

 surface from which the designation is taken arises from the 

 dermal sarcode originally presenting this fibro-reticulated 

 structure in a soft state becoming densely charged with the 

 flesh -spicules. Although the specimen bore no label, it was 

 found among Dr. Bowerbank s specimens from the south 

 coast of Australia; and therefore this may have been its 

 " locality." 



Stelletta globostellata, Crtr. (PL XIV. fig. 5, a-h.) 



Compressed and corrugated on the surface, probably from 

 desiccation ; smooth above, rough below, where it was torn 

 off from the object on which it grew. Surface hard, even, 

 dimpled by a vermiculated reticulation in low relief, the 

 interstice of which presents a pore-opening. Vents con- 

 gregated in one part of the surface. Spicules of two kinds, 

 viz. skeletal and flesh -spicules : — 1, body-spicule, acerate, 

 sharp-pointed, fusiform, smooth, curved, 63 by l£-1800ths 

 inch in its greatest dimensions (fig. 5, a), 2, zone-spicule 

 not so long, shaft straight, 45 by l^-lSOOths inch, 

 pointed at one end, trifid at the other, arms thin, long, 

 and horizontal, 13-1800ths in length (fig. 5, b). Neither 

 anchors nor forks seen. Flesh-spicules of two forms, viz. : — 

 1, a beautifully clear crystalline globostellate, whose rays are 

 conical, long, smooth, and sharp-pointed, being about one 

 third of the diameter of the whole body, which is 12-6000ths 

 inch (fig. 5, c and e ) ; 2, small stellate, about 3-6000ths inch 

 in diameter (fig. 5 d and /). Incrustation white, hard, and 

 comparatively thick, viz. l-96th inch in vertical diameter 

 (fig. 5, ijj h)j contracting strongly in its white colour with 

 the internal substance, which now, in its dried state, is dirty 

 yellow. Size of entire specimen about 3 inches in horizontal 

 diameter by \\ thick. 



Hab. Marine. On coral-reef. 



