OE SOUTHERN INDIA. 163 



78. — V, Rochehruni (Tapes icl.^ Zittel)^ I would rather suspect to be a small CalUsta than a 

 member of the tapesin^, 



79. — Donacilla compressa^ d^Orb.^ (Pal. fran9.^ iii^ pi. 376^ figs. 3-4); belongs apparently to 

 Baroda of the tapesin^, 



80. — Psammobia impar, Zittel^ {Denksch. Akad., Wien, xxiv, pt. ii, p. 120,) is a species of 

 the sub-genus Icanoiia, and the species may provisionally stand as Baroda \Icanotia'\ impar, 

 Zittel, sp., for it is not very improbable that Matheron's Solen elegans is also an Icanotia, though 

 quite distinct as species. 



^l.—Psammohia discrepans, Duj.^ (Mem. Soc. Geol., France, ii, p. 223, pi. ii, fig, 2). The 

 figure of the fragmentary shell leaves one in doubt whether the species may not be one of the 

 PSAMMOBimjE, but that of the cast is more indicative of a species of Icanotia. If d'Orbigny's 

 figure (Pal. fran5., iii, pi. 381, figs. 3-5,) is correct, there can be little doubt about this. 



^%,—Solen inflexus, Duj., (ib. p. 202, pi. ii, fig. 4,) is also more likely a Baroda%\\n.n anything 

 else. In such cases as this, where imperfect casts are considered to be sufficiently characteristic 

 of a species, there is, however, a great difficulty to distinguish between the tapesin^ and some 



PHARELLINJE of the SOLENID^, 



S^.'—Capm Armudi, H. Coq., (Bull. Soc. Geol., France, vol. xvi, p. 1000). The description 

 indicates a species of Icanotia. 



84-85.— P^«?^m. Suessi, Zitt., (Denksch. Akad., Wien, xxiv, pt. ii, p. 121, &c.), and Tellina 

 Venei, d'Arch. (Bull. Soc. Geol, France, 2nd ser., vol. xi, pi. ii, figs. 1-2,) are typical species 

 of Baroda, 



86. — Circe discus, M^i\\., sp. ( Zittel in Denksch, Akad., Wien, xxiv, pt. ii, p. 128, pi. iii, 

 fig. 7), is a C^primeria, Pictet and Campiche (Pal. Suisse, 3™^ ser., 3«iept.^p. 197^) discuss the 

 question as to the discrepancy in the existing accounts of this species at length, and very properly. 

 There can be little doubt that the species described and figured by Matheron (Cat., p. 144^ pi. 13, 

 fig. 12,) is the true discus of Zittel, for he compared the Gosau specimens with one sent to him 

 by Matheron himself. I have myself exposed the pallial line on three of the Gosau specimens 

 and I can testify to the correctness of Zitte^s drawing (in fig. 7<?). I would not call the pallial 

 impression an entire one ; it is distinctly insinuated, though the sinus is very shallow and rounded 

 at least as far as the impressions on the casts go ; we do not find it sometimes stronger in species of 

 CytJierea or Venus. Variations of that kind, as I had already often mentioned, are by no means 

 rare. It is more likely that d^'Orbigny was mistaken in his figure (4, pi. 379), for in any of the 

 species of Cyprimeria that I have seen, I have not observed such a broadly rounded sinus ; still 

 there is no reason that the form could not occur, and if this shape of the sinus be confirmed the 

 form must be considered to be a different species under d^Orbigny's name Cyp. numismalis. 



^1 .—-Arcopagia Cenomaniensis^ d^Orb., (Prod., ii, p. 158,) said to be allied to Arc. (Cyprimeria) 

 discus of the same author. 



^^•^"^.-^Arcopagia rotundata, d'Orb., (Pal. fran9., pi. 379, figs. %-! ,) and Circe concentrica, 

 Zittel, (loc. cit., p. 130, pi. 4, fig. 1,) are CyprimericB. 



90.-^ — Circe duhiosa, Zittel, (ibid. fig. 2). I think Zittel is correct in referring this species to 

 the same genus as the last named species. I succeeded in breaking up a specimen partially devoid 

 of shell. The left valve distinctly shows two thin diverging teeth under the umbo and a third 

 posterior long one, being very thin ; in the right valve I can also notice two divergino' teeth, but 

 they are not very distinct ; there are no other teeth under the lunula, so the species is not a Circe, 

 It, on the whole, somewhat resembles Fe7ius miciformis, Miill., and is, therefore, still more 

 likely a Mercenaria. The beaks are incurved, but the edges of the lunula are, as in Cyprimeria^, 

 straight, not excavated. 



* I sliall coiitiuiie tlie numljers, tliougli tliey must uot as yet be accepted as indicating so many distinct species. 



