Mr. H. J. Carter on the Gumminea?. 29 



spicules (in Selenka's species calcareous), of different forms 

 according with the species, or none at all as in the Halisarcina? ; 

 but in no instance a fibrous skeleton, like that of sponges in 

 general ; indeed no skeleton at all, which is the chief distin- 

 guishing point between the Gumminese and true sponges. 



About the specimen dredged up on board the ' Porcupine ' 

 are : — besides the well-known Coccoh'ths, a great number of that 

 species first described and figured by Schmidt as " Bhabdoltthes" 

 (Annals, 1872, vol. x. p. 359, pi. xvii.), for which I would 

 propose the name of E. Schmidtii, after its well-known disco- 

 verer (PI. I. fig. 17) ; also a number of calcareous spherical 

 cells lined with minute cellulse, for which I would propose 

 provisionally the name of Sphosoliihes abyssi (fig. 18), as 

 they may perhaps hereafter, be found to be embryos of the 

 Globigerino3 or some other deep-sea foraminifer. They are, 

 however, very numerous and of all sizes below the largest, 

 which is that figured. 



The fragments and spicules of the other sponges about this 

 specimen, viz. Dictyocylindrus abyssi, n. sp. (PI. I. fig. 2, e), 

 DesmaceUa annexa, Sdt. (Florida) (fig. 2, e), Renter -a fibulata, 

 Sdt. (fig. l,e), and Cliona abyssi, n. sp. (fig. l,c?), will be de- 

 scribed and figured on a future occasion. 



EXPLANATION OF PLATE I. 



Fig. 1. Portion of Lophohelia prolifera, imbedded in Corticium abyssi, 

 n. sp., dredged up on board H.M.S. ' Porcupine ' in the " chops " 

 of the English Channel ; depth 500 fathoms, muddy bottom. 

 Natural size, a, Lophohelia ; b, Corticium abyssi ; c, vents of 

 the same ; d, fenestra 1 openings of Cliona abyssi, n. sp.,in Lopho- 

 helia ; e, portion of Reniera Jibidata, Sdt. ; /, fragments of large 

 spicules imbedded in the Corticium. 



Fig. 2. The same, opposite side, nat. size : a, Lophohelia prolifera ; b, Cor- 

 ticium abyssi ; c, vents of the same ; d, portions of a Farrea 

 which grew on the Lopholielia before the whole became im- 

 bedded in the Corticium ; e, portions of Dictyocylindrus (Bk.) 

 abyssi, Cart., n. sp., and DesmaceUa annexa, Sdt., filling and sur- 

 rounding the tube net of Farrea ; f, portion of Corticium filling 

 tube net of Farrea ; g, fragment of large spicule imbedded in 

 Corticium ; h, fragment of Reniera Jibidata, Sdt. 



Fig. 3. Corticium abyssi, biternate spicule of, lateral view. 



Fig. 4. The same, average largest size of biternate spicule : a, portion of 

 shaft supporting the cuticula ; b, arms broken off ; c, inner portion 

 of shaft ; d, central canal. Scale l-12th to l-6000th of an inch. 



Fig. 5. The same, vertical view of head of biternate spicule : a, main arms, 

 not spined ; 6, secondary arms, spined. Same scale. 



Fig. 6. The same, young form of biternate spicule, spineless : a, central 

 inflation. 



Fig. 7. The same, birotulate with four recurved arms, about l-5000th of 

 an inch long. Scale l-12th to l-6000th of an inch. 



Fig. 8. The same, portion of body-substance : a, ovoid cells, and b, biro- 



