530 DR. J. E. GRAY ON SPONGES. [May 9, 



B. Tube formed of fascicules of filiform spicules placed in various 

 directions, forming an irregular network like the lid of the 

 tube, and not strengthened with any raised transverse or ob- 

 lique ridges or fringe at the edge of the aperture, and without 

 any free barbed filament at the base. 



2. CORBITELLA. 



The tube clavate, rather irregular, rounded at the end, formed of 

 slender fascicules of open elongate filiform spicules, placed in longi- 

 tudinal, transverse, and oblique directions, forming an irregular net- 

 work. 



Alcyoncellum, Quoy & Gaim. (not DeBlainville). 



Euplectella, sp.. Gray, Ann. & Mag, N. H. 1806. 



This genus chiefly differs from Euplectella in the want of the 

 well-marked longitudinal and transverse bundles of spicules, which 

 are to be observed in all the specimens of different ages of E. asper- 

 gillum that have come under my observation. 



CORBITELLA SPECIOSA. (PI. XXVIII. fig. 1.) 



Alcyoncellum speciosum, Quoy & Gaim, Voj. Astrol. p. 302, Zoo- 

 phytes, t. 26. f. 3, 1833 (very bad); Lamk. An. s. Vert. ed. 2, ii. 

 p. 589 ; Bowerb. B. S. f 185, 187, 188, 195? 



Hab. Molucca (M, Merkus ; Mus. Paris). 



Quoy and Gaimard thus describe the only specimen of this 

 sponge yet known in Europe : — " Cette singulicre production re- 

 prcsente un cylindre creux, de sept a huit ponces d'etendue, en 

 forme de Phallus, arrondi et un peu dilate a une extrcmite, ouvert ti 

 I'autre, a parois mince, formee de filets tres delies, luchement aecole's 

 les uns aux autres, entrecroise's dans tous les sens, de maniere a 

 former de nombreuses mailles arrondies, presque regulieres comme 

 celles de la dentelle ou bien des sieges tisses en rotang." — Zoophytes, 

 ii. p. 303. 



Professor Wy ville Thompson has most kindly sent me a photograph 

 of this specimen, which is here copied (PL XXVIII. fig. 1), and 

 which shows that it is quite distinct from the Philippine Sponge. 



MM. Quoy and Gaimard's figure is very imperfect, and probably 

 misled Prof. Owen ; for he observes, when describing Euplectella 

 aspergillum, that " If the basal aperture of the cone were open, the 

 resemblance to some of the known Alcyonoid sponges would be very 

 close, especially to that called Alcyonellum gelatinosum by M. 

 DeBlainville {Alcyonellum speciosum, Quoy & Gaim.); its closure 

 by the reticulate convex frilled cap in the present instance establishes 

 the generic distinction." — Trans. Zool. Soe. iii. p. 205. 



But the specimen figured by MM. Quoy and Gaimard has a "re- 

 ticulate convex cap." And this is not the only mistake in this para- 

 graph ; the "basal aperture" is the apex of the sponge. Alcyo- 

 nellutn gelatinosum (which should be Alcyoncellum gelatinosum, 

 Blainville) has no affinity to Alcyoncellum speciosum of Quoy and 



