458 Dr. J. E. Gray on the Classification of Sponges. 



Euplectellaclas, as I had not the opportunity of examining the 

 sponges, and only knew them from having seen them in Paris 

 and by the photographs of Dr. Wyville Thomson. 



Dr. W. Thomson has since described them as a genus, 

 observing, " as I am prechided from using either of Dr. Gray's 

 names, I substitute Habrodicft/on, which I had in MS. before 

 I saw Dr. Gray's paper." Why he is prechided is not stated. 

 When he sent me the photographs, with the permission to 

 describe and name them (seeProc.Zool.Soc. 1867, pp. 530,531), 

 he did not communicate any name to me, or I would gladly have 

 used his generic name ; but I fear that now the question is out 

 of both our hands, and must follow the recognized rules of 

 nomenclatm-e. 



Fam. 10. Askonematidae. 



Sponge fixed, cup-shaped, formed of abundant elongate 

 spicules, with scattered hexaradiate spines often denticulated on 

 the edge of the rays ; spicules with bifurcate ends repeatedly 

 forked, and spherical groups of elongate spicules, which are 

 capped at the end. 



Askonema, Kent, Quart. Joum. Microsc. Science, 1870. 



D. Sponge Jixedj formed of fusiform spicules imbedded in 

 keratose matter. Hexaradiate sjnnes in the sarcode. 



Fam. 11. Carteriadse. 



Sponge cup-shaped, formed of abundant netted fibres con- 

 taining many fusiform spicules, with scattered six-rayed stel- 

 late spicules, ending in a circle of reflexed lobes ; the rays are 

 often abortive, producing a cylindrical axis terminating at each 

 end in the reflexed lobe, and hence they have been called birotu- 

 late spines. Mr. Carter has found rudiments of side branches 

 on the central axis, and some specimens have all the six lobes 

 perfect and furnished with rays at the end, showing that the 

 birotulate specimens are only the result of the more or less 

 complete abortion of the lateral lobe, and that it belongs to 

 this order. 



Carteria, Gray, P. Z. S. 1867, p. 540. 



Fam. 12. Axidse. 



Sponge arborescent, branched, with hexaradiate subcubical 

 spicules, as if formed of six cubes placed on each side of a 

 central one, and with three rayed stellate spicules. 



Axos = Echinosp)ongia, Gray, Ann. & Mag. N. H. 1870, 

 vi. p. 272. 



