Grantia. 
ZOOPHYTA. SPONGIAD.E. 
5S5 
Spongia comp. Fab. Fauna Groen. 448 — S. foliacea, Mont. Wern. 
Mem. ii. 92. t. xii. — S. comp. Grant, NewEdin. Phil. Journ. i. 166.-ii. 
t. ii. f. 11, 12, 13-23.— *On the under side of rocks near low water- 
mark, common. 
Length seldom above an inch, white, ovate, and of uniform thickness 
throughout. The external surface is crowded with numerous spicula, thick, 
and bent at one end, tapering to the other ; the pores on the inner surface 
are larger, and the spicula triradiated ; besides these two well-marked forms 
of spicula, there are others linear, pointed, and of unequal lengths It is 
probable that the radiated spicula of this or the following species constitute 
the Asterias of Walker, Test. Min. t. hi. f. 90. 
113. G. hotryoldes. — Tubular, branched, inosculating, with 
subclavate terminal simple orifices ; spicula triradiated. 
Spongia hot. Sol. Ell. Zooph. 190. t. 58. f. 1-4 — S. complicata, Mont. 
Wern. Mem. ii. 97- 1. 9. f. 3, 4. — At the roots of fuci, about low water- 
mark, not uncommon. 
Branches in tufts, of a white colour, round, in some places adhering ; ex- 
ternally the triradiated spicula are numerous ; internally they are few, and 
the pores more obvious. The late Mr Montagu, to whom 1 communicated 
specimens of this species, having employed lenses with very weak magnify- 
ing powers, did not detect its peculiar spicula, and was in consequence led 
to constitute a spurious species. 
114. G. dZmto.— Tubular, slightly contracted towards the 
terminal aperture, the margin of which is ciliated. 
Spongia cil. Fab. Fauna Groen. 448 — S. cornata, Sol. Ell. Zooph. 190. 
t. Ivhi. f. 89. Mont. Wern. Mem. ii. 88.— -On fuci, near low water- 
mark, not uncommon. 
About half an inch in length, and |th in thickness ; the surface is closely 
covered With linear pointed spicula, having a terminal direction ; in the sub- 
stance of the sponge, besides these linear, there are other triradiated spicula. 
The internal surface is full of irregularly shaped pores. 
115. G. piilverulenta. — Ovate, thick, pulverulent, villous. 
Spongia ananas, var. Mont. Wern. Mem. ii. 97- t. xvi. f. 3. — On coral- 
lines, rare. 
The substance of this species is thicker than the preceding, and the linear 
spicula on the surface are longer and more crowded; Montagu found his 
specimens on Cellaria scruposa ; mine were obtained from Sertularia cupressina 
Zetland. 
116. G. nivea. — Sessile, encrusting, with minute pores and 
circular orifices 5 spicula triradiate and (j^uadriradiate. 
Spongia nivea. Grant, New Edin. Phil. Journ. i. 168-11. t. ii. f. 14, 15, 
16 Under surface of sheltered rocks, Prestonpans Bay, Frith of 
Forth. 
Crust in patches, one or two inches in diameter, and about two lines in 
thickness ; the orifices are slightly elevated, thickened at the base, and very 
thin towards the margin ; spicula unequal, the side-arms of the quadriradiate 
ones usually short. 
Sponges, the situation of which in the three preceding genera is doubtful. 
I. S. With very slender, dichotomous branches, digitated at 
3 
