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TERTIARY FAUNA OF FLORIDA 



difference lies in the spoon-shaped process for the resilium in the latter, while 

 in the former two the resilium is directly applied to the valve. 



Thecodonta ? (Dicranodesma) calvertensis Glenn. 



PLATE 45, FIGURES 23, 24. 



Miocene of Maryland at Plum Point; Maryland Geological Survey. 

 This is a peculiarly solid little shell, convex, polished, and unusually tri- 

 gonal, with a particularly solid hinge, conical anterior, and stout lamelliform 

 posterior teeth, and small adductor scars. It measures 4.6 mm. in length, 3.5 

 in height, and about 3 in diameter. It was obtained by Mr. L. C. Glenn of 

 the Survey, who will fully describe it in a forthcoming publication of the 

 Maryland Survey. 



Genus ROCHEFORTIA Ve'lain. 



Montacnta (sp.) Turton, Dithyra Brit., p. 60, 1822 (M. bidentata Mtg.). 

 Anatina (sp.) Brown, 111. Conch. Gt. Brit., ist ed., 1827. A. bidentata (Mtg. sp.) Brown, 



of. tit., pi. ii, figs. 8, 9. 



Tcllimya, Sect. ii. (sp.), Brown, III. Conch. Gt. Brit., 2d ed., p. 107, 1844. 

 Rochcfortia Velain, Comptes rendus, July 24, 1876; Fauna St. Paul et Amst, p. 133, 1877. 



Type R. australis Velain, of. tit., p. 133, pi. v., figs. 9-11 (bad) ; Bernard, Bull. Mus. 



d'Hist. Nat., 1898, p. 82, fig. 4. 

 Tcllimya H. and A. Adams, Gen. Rec. Moll., ii., p. 478, 1857, type T. bidentata Mtg. ; 



not of Brown, 1827. 

 > Sphenalia S. Wood, Suppl. Crag Moll., iii., p. 126, 1874. Type 5. donacina S. Wood, 



loc. tit., Jeffreys, P. Z. S., 1881, p. 698; Fischer, Man. Conch., p. 1027, 1887. 

 Mysclla Angas, P. Z. S., 1877, p. 176. Type M. anomala Angas, op. tit., pi. xxvi., fig. 22 



(very bad) ; Dall, Proc. U. S. Nat. Mus., xxi., pp. 876, 890, June, 1899. 



The name Telliuiya, as of Brown, has had a considerable currency, owing 

 to Adams's use of it with T. bidentata as the type. But T. bidentata was not 

 included among the original Tellimyas of 1827. It was referred to Anatina 

 by Brown in the publication in which he first proposed the genus Tellimya, and 

 consequently cannot be used as a type for that genus. 



The original Tcllimya was divided into two * sections by its author, contain- 



* By a very natural mistake Miss Bush (Science, N. S., x., p. 250) has stated that 

 Brown (in 1844) divided his genus Tcllimya into three sections. The supposed third 

 section (Brown, p. 107) is really a section of the family Mactracea and not of the genus 

 Tcllimya; and the confusion arises from the fact that Brown subdivides not only the 

 genus but the family into groups which he calls sections, which are printed in the same 

 type and have their Roman numerals frequently incorrect. 



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