OF SOUTHERN INDIA. 99 



10. Foegia, Gray, 1840. Only the vimbones of the A-alves exposed on the 

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

 F. agglutinans and Zebueusis, are, judging from Chenu's figm-es, most probably 

 identical. 



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

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

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

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



10«. Penicilliis, Gray, 1840: Tubercle in front of the umbones of the valves 

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

 Clepsydra, seems to me quite imnecessary. Brech. Javamis 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 BRECHITINJ-: live buried 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 GASTRocb.eninje, Pictet, (Pal Suisse, 3""^ Ser., 3"« jrt., p. 17,) 

 quotes 16 species, among which we find representatives of Spengleria, Eocellaria, and Gastrochcena. 



1-2. — Gast. arcaformis and Sanctcc-crucis, P. and Camp., are the earliest knouTi representatives 

 of Spenyleria. 



3-18. — Gast. dilaia, Desh., G. sinuosa, Pict. and Camp., G. Valangiensis, P. and C, G. asine- 

 arnm, P. and C, G. Rathieriana, Cott., G. Matronensis, d'Orb., G. gauUina, P. and C, G. brevis 

 P. and C, G. Boyanensis, d'Orb., (alias Boi/and), G. oslrea, Gein., and G. pidillJJormis, Reuss, 

 belong to Eocellaria ; G. i^yriformis, Mant., G. Marticenms, Math., and G. temtis of Geinitz, are 

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

 be said of Gast. Essetisis and Tornacensis of Ryckholt, (Mel. paleont., 1"^ pt., 1852, p. 119). 



Some other species, like Gast., or Fisttilaua, amplishana, Goldf., Gast. voracissima , Miiller, 

 &c., I have already noticed when speaking of the TEREDINj:. Ryckholt (Mel. paleont., 

 loc. cit., p. 118, pi. 5, figs. 19-22,) gives, among others, the figure of a valve which he states 

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

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

 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 Ryekholt's statement, I 

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

 of the G.iSTROCn.ENiyjE and not to the teredi?<in.e, to the latter of which they have undoubtedly a 

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

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

 Gast. ci/lindrica, Fahrenkohl, which is said to occur in Neocomieu beds near Moscow, these 

 being, however, by several other able geologists referred to the Jurassic period. Gast. sitiuosa of 

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



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

 one, 7^ gnttula, and the tube of another species probably belonging to the same genus. 



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

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



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