Sponges from the Atlantic Ocean. 4.09 



represent a distinct sponge. I might also add that in no .sp(;iigc 

 have I ever seen these tortuous acerates grouped together as 

 above described below tiie surface, excejit in Ift/meraphia 

 vermicuhita, Bk., and its variety erecta (PI. XV. Hg. 2G, ^), 

 where their great inferiority in size and tlieir forming part of 

 a distinct structure, from the midst of which projects large 

 acuates, shows at once that they arc not Ophimpkiditefi tor- 

 tuosus. At the same time, as the laminiform species, viz. Hy- 

 meraphia vermicitlafa, Bk., grows on the surface of hard 

 objects, such as pebbles, and other sponges, indiscriminately, 

 and there are tortuous acuates mixed up with the tortuous 

 acerates in Ophirapliiditcs^ it may still be a question whether 

 this may not be after all a transformation of the spicules of 

 H. vennicuJata with which a few of the trilids of Pacfiastrella 

 abyssi have become accidentally mixed. 



Be this, however, as it may, after having described Ophi- 

 raphidites tortuosus as part of the dredgings of the ' Porcupine,' 

 the great point of interest that attaches to them is that such 

 spicules are found fossilized in the Upper Greensand of Haldon 

 Hill, near Exeter, in the Mid-Pliocene or Bruxellien " etage " 

 about Brussels, and in the Cretaceous strata of Westphalia, 

 in Germany, respectively. In my illustrations of the fossil 

 sponge-spicules of the Upper Greensand of Haldon Hill, near 

 Exeter, I have figured one ('Annals,' 1871, vol. vii. p. 131, 

 pi. X. hg. 79) under the name of "E,sperites giyanteiis,^^ con- 

 ceiving it tlien to be, from its sigmoid shape, a gigantic S- 

 sliaped bihamate (fibula) of an Esjjeria^ whereas now I see 

 that it is a spicule like those of Ophiraphidttes tortuosus ; hence 

 the term '"''Esperites gig aniens'''' should be erased, and that of 

 OphirapJiidifes tortuosus snhst'ituted ior it. The specific name 

 ^\(/iganteus " cannot be retained, because its size corresponds 

 with that of the spicules of the existing Oj)hiraphidites. I 

 next observed it in M. A. Rutot's illustrations of fossil sponge- 

 spicules " de I'etage Bruxellien " about Brussels (Ann. de la 

 Soc. Malacologique de Belgique, t. ix. 1874, pi. 3. figs. 5 & 29), 

 confirmed by its presence in some of the spiculiferous sand it- 

 self (kindly sent to me by M. E. Vanden Broeck), wherein it is 

 plentifully pi-esent ; lastly, in Prof. K. A. Zittel's illustrations 

 of sponge-spicules found about a specimen of Cosloptychiuni 

 agaricoides from the Quadersandstein of Westphalia ( Abhand- 

 lungen der k. bayer. Akad. der W. ii. CI. xii. Bd. iii. Abth. 

 Taf. 4. hgs. 25 & 26, 1876). Schmidt has also figured them 

 (Grundz. Spongienf. d. atlant. Gebietes, 1870, p. 24, Taf. iii. 

 fig. 3, c), in connexion with Corallistes Bowerbankii (C. typns^ 

 Sdt.), as they certainly are no part of this s])onge. To M. 

 Butot and Prof. Zittel I am greatly indebted for a copy of 



31* 



