Knowledge of the Spongida. 351 



parts, so that the vents were not seen. Skeletal spicules of 

 three forms, viz. : — 1, body-spicule, acerate, sharp-pointed, fusi- 

 form, smooth, curved, 157 by 4-1800ths inch in its greatest 

 dimensions (fig. 2, a) ; 2, zone-spicule, almost equally long, 

 shaft curved, 160 by 4-lS00ths inch, pointed at one end, tritid 

 at the other, arms simple, pointed, carried very much in front 

 and rather curved inwards corolla-like, 14-1800ths inch long 

 (fig. 2, b) ; 3, anchors and forks as usual, with long thin 

 shafts (fig. 2, c and d). Flesh-spicules of two forms, viz. 

 bacillar and stellate, both very small ; the former 2-6000ths 

 inch long (fig. 2, e), and the latter the same in diameter 

 (fig. 2,/j. Incrustation very thin (fig. 2, g 7 h). 



Hob. Marine. 



Log. Freemantle, west coast of Australia. 



Obs. This specimen is in the Bovverbank general collection 

 at the British Museum, and was labelled " Freemantle, W. 

 Australia. Clifton." The smoothness and thinness of the 

 cutis is probably owing to the minuteness of the flesh-spicules 

 with which the dermal sarcode is charged. 



Stelletta bacilli/era, var. robusta, Crtr. 



(PL XIV. fig. 3, a-f.) 



Conical compressed ; head expanded, fiat, elliptical, and cor- 

 rugated from the specimen being dry, sides smooth and fur- 

 rowed to a point. Vents few and very large, each contracted 

 by a wide sarcodic diaphragm, situated in the fiat part. 

 Spicules of two kinds, viz. skeletal and flesh-spicules: 



1, body-spicule, acerate, sharp-pointed, fusiform, smooth, 

 curved, 93 by lf-1800ths inch in greatest dimensions (fig. 

 3, a) ; 2, zone-spicule, about the same length, shaft straight, 

 about 110 by 2-1800ths inch, pointed at one end, tritid at the 

 other, arms simple, horizontal, recurved, each 3-1800ths long 

 (fig. 3, b) ; 3, anchors alone, no forks seen, anchor-head flat- 



tish and expanded, shaft short (fig. 3, c). Flesh-spicules of 



three forms, viz. : — 1, bacillar, fusiform, microspined, 11 by 

 2i-G000ths inch in its greatest dimensions (tig. 3, d and g) ; 



2, minute, stellate, about 2-6000ths inch in diameter (fig. 3, e 

 and h)) 3, minute, acerate, curved, sometimes undulated, 

 varying in size under 30-6000ths inch (tig. 3,/). Incrusta- 

 tion very thin. Size of entire specimen 4 inches high and 6 

 by 3 inches in diameter across the head or base of the cone- 

 shaped mass. 



Hob. Marine. 



hoc. Ports Elliot and Adelaide, S. Australia, 



Obs. Of this species there are two dozen specimens in the 



