OP SOUTHEEN INDIA. 29 



lOi Foegia, Gray, 1840. Only the iimbones of the valves exposed on the 

 tube, more or less covered by a tubercle in front of them. The two species, 

 F, agglutinans and Zebuensis^ are, judging from Chenu's figures, most probably 

 identical. 



Gray distinguishes a sub-genus, Arytene, (including Foeg. Rechiziana and 

 tuber culatd)^ said to differ from Foegia, as restricted, by its simple disc, but in both 

 the species the marginal tubuli are considerably projecting, and united to a simple 

 fringe. The sub-generic distinction appears to me scarcely to have any value. 



10a. Fenicilliis, Gray, 1840. Tubercle in front of the umbones of the valves 

 obsolete. The separation of P. strangulatus, Chenu, again as a separate sub-genus. 

 Clepsydra, seems to me quite unnecessary. Brech, Javanus gives an example of 

 this, for in this species there are occasionally two fringes developed round the disc, 

 while in other specimens of the same locality there is only one* 



All the BRECRiTiN^. live bmied in sand and mud, in a more or less perpendicular 

 position. They are comparatively rare shells, and a comparison of numerous 

 specimens of the various species would probably show no necessity for separating 

 even those three generic divisions which I have here adopted. There are a few 

 tertiary species known, but none with certainty from the cretaceous or older 

 deposits. 



Of the first sub-family, the gastrocejenin^j Pictet, (Pal Suisse, 3"^^ Ser., 3^^ pt., p. 17,) 

 quotes 16 species, among which we find representatives of Spengleria, Rocellaria^ and Gastrochcena, 



1-2. — Gast. arcaeformis and Sancta-cruciSj P. and Camp., are the earliest known representatives 

 of Spengleria. 



3-18. — Gast. dilata, Desh., G. sinuosa, Pict. and Camp., G. Valangiensis , P. and C*, G. astrm- 

 arum, P. and C, G. Batliieriana , Cott., G. Matronensis, d^Orb., G. gauUina, P. and C, G. brevis, 

 P. and C, G. Moyanensis, d^Orb., (alias Roy ana), G. ostre^B, Gein., and G. pistilliformis , Reuss, 

 belong" to Bocellaria ; G . pyriformis , Mant., G. Marticensisy Math., and G. tenuis of Geinitz, are 

 doubtful, but the excavations also resemble in every respect those of Rocellaria. The same can 

 be said of Gast. Msensis and Tornacensis of Eyckholt, (Mel. paleont., 1®^^ pt., 1852, p. 119). 



Some other species^ like Gast., or Fistulana, ampliishcena, Goldf., Gast. voracissima, Miiller^ 

 &c.^ I have ah-eady noticed when speaking of the teredin^. Ryckholt (MeL paleont.^ 

 loc. cit.j p. 118^ pi. b, figs. 19-22^) gives^ among others, the figure of a valve which he states 

 to have been found in the tube referred to Gast. amphisbcena of Goldfuss and Geinitz. The 

 valve is certainly not that of a Teredo, but neither has it the appearance of a Rocellaria, 

 unless it is very much worn off; it would more probably be that of a Clavagella, but there 

 are no tubuli known to occur on the end of the tube. In spite of Ryckholt''s statement^ I 

 think, there is more decisive proof required to show, that those tubes really belong to a species 

 of the GASTRoch^niNjE and not to the teredinin^, to the latter of which they have undoubtedly a 

 far greater resemblance. Gastroch. socialis of Eichwald has been subsequently placed by the same 

 author in the genus Teredo. In Leth. Ross, xi livr., p. 721, the same author, however, describes a 

 Gast. cylindrica, Fahrenkohl, which is said to occur in Neocomien beds near Moscow, these 

 beingj however, by several other able geologists referred to the Jurassic period. Gast. sinuosa of 

 Pictet and Camp, is also mentioned here from some other Neocomien beds." 



19. — To the 16 known species of Rocellaria I shall add from our South Indian cretaceous rocks 

 one, R. guttula, and the tube of another species probably belonging to the same genus. 



20. — Zittel described from the Gosau deposits ^Fistulana tiibulosa, which has now to be called a 

 Gastroclmna (Denksch. Akad., Wien, 1865, xxiv, pt. 2, p. 108, pi. 1, fig. 1). 



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