the Ccqye of Good Hope and Panama. 253 



It is further interesting to find a figure of this spicule in 

 Dr. Bowerbank's ' British Spongiadge ' (voL i. p. 270, pi. xi. 

 fig. 244), which is stated to have been " repeatedly found in 

 the matter obtained by washing the roots of Oculina rosea and 

 other corals from the South Sea by my friends Messrs. 

 Mathew Marshall, Legg and Ingall ; but the sponge from 

 whence it is most probably derived has never yet been deter- 

 mined," &c. With this Dr. Bowerbank gives two other 

 figures of similar kinds of spicules, and considers that they 

 " indicate the existence of a peculiar tribe of sponges with 

 which we are at present entirely unacquainted." That 

 " tribe," as I have above stated, is probably Schmidt's 

 Gumminese. 



Corticium Ktttonn, n. sp. PI. XV. fig. 48, a, h, c. 



Spicule stout, consisting of a short shaft from one end of 

 which 2, 8, or 4 arms spread upwards and outwards en fleur-de- 

 lis (fig. 48, rt, i, c). Arms about twice the length of the shaft, 

 and all parts, with the exception of that about tlie junction of 

 the arms with the shaft, tliickly covered by stout vertical 

 short spines. Size of specimens — total length 19-1800ths 

 inch ; shaft 11 by 2-1800ths inch in its greatest diameters. 



Ohs. The arenaceous deposit from which these beautiful 

 spicules were obtained came from the neighbourhood of Colon, 

 Panama, and was sent to Mr. Kitton, of Norwich, chiefly for its 

 richness in Diatomacete. They are so exquisitely mounted, 

 and so perfect, that nothing further in this respect could be 

 desired ; while they are so characteristically like those of 

 Corticium abyssi which I have described and figured in the 

 'Annals' (vol. xii. July 1878, p. 19, pi. i. figs. 3-5), that 

 I do not think I can be wrong in giving the name above 

 mentioned to the sponge from which these were originally 

 derived. 



To the likeness in nature of the arenaceous deposit from 

 which these spicules were obtained to that of the Agulhas 

 Shoal dredged up by Dr. Wallich, and of both to the " green- 

 sand " of the Chalk Formation, I have above alluded. 



Nor should I omit to add here, respecting the probable 

 existence of the Gummineas themselves in the " grecnsand 

 deposit," that the fossil spicules termed " J/omY/fes " (Annals, 

 vol. vii. 1871, p. 132, pi. ix. figs. 44-47, now that I am better 

 acquainted with the existing species) seem to me to have 

 belonged to sponges of this kind ; while I have lately found 

 acerate and short-shafted, three-armed, headed forms of tiiis 

 spicule in some powder from tlie interior of a flint from 



