112 Mr. H. J. Carter on 



hand, the characteristic anchovate is so short and robust that 

 it forms by far the most prominent object among the flesh- 

 spicules. There is also, as above stated, a small equianchorate 

 and a paraboliform spicule like a bihamate ; but as it is pos- 

 sible that these may in some way be related to the robust 

 equianchorate, I have here also not included them among the 

 spiculation, although the representations to which I have alluded 

 are given, but these are for the use of future observers. The 

 arms of the large equianchorate, too, are stated conjecturally 

 to be " petaloid," because their transparency and their refrac- 

 tion of the light as it passes through them renders their real 

 forms so indistinct. 



Halichondria scabida, n. sp. (PI. IV. fig. 4, a-p, and 

 5, a-g.) 



Specimen globular, compressed, sessile (fig. 4, a). Con- 

 sistence tough, fibrous. Colour now brown externally, yel- 

 lowish internally. Surface even, undulating, consisting of a 

 dense, smooth dermis, more or less covered with suboval and 

 subcircular areas like small scars, separate, or together in 

 juxtaposition (fig. 4,bb); area circumscribed by a slightly 

 raised rim, subtended by a delicate cribriform layer of the 

 dermal sarcode, varying in size under \ in. in diameter 

 (fig. 4, k, £, m) . Pores confined to and synonymous with the 

 holes of the cribriform areas, each pore about 1-300 in. in 

 diameter (fig. 4, k, m) . Vents here and there. Internally, 

 subdermal cavities strongly developed, consisting of a cancel- 

 lated fibrous structure, in which the folds occupied by spiculous 

 fibre, arching over and intersecting each other, support the 

 pore-areas above (fig. 5, a b) , which thus open into the excre- 

 tory canals below (fig. 5, c) , through which the arching or cir- 

 cular folds (fig. 5, d) are continued to the vents in the opposite 

 direction (fig. 5,g). Parenchyma fibro-pulpy, of a yellow 

 colour, traversed plentifully by the branches of the excretory 

 canal-systems. Spicules of five forms, viz. : — 1, skeletal, acuate, 

 slightly curved, head oval elongated, with contracted neck, 

 passing into a fusiform shaft, which terminates gradually in a 

 sharp point, 51 by l-6000th in. in its greatest dimensions, head 

 a little less in diameter than the shaft (fig. 4, d) ; 2, subske- 

 letal, simply acuate, curved, gradually sharp-pointed, spined 

 throughout, especially about the obtuse end, 43 by 1 ^-GOOOths in. 

 (fig. 4, e) ; 3, the same, but much smaller, viz. 20 by 

 l^-6000thsin. (fig. 4,f) ; 4, flesh-spicule equianchorate, with 

 slightly angulated, curved fusiform shaft, and three diverging 

 knife-shaped arms or flukes at each end, 7-6000ths in. long 

 (fig. 4, g, i) ; 4, ?-small size of same (fig. 4, h) . No. 5 abounds 



