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TERTIARY FAUNA OF FLORIDA 



prominent, exterior sculptured with moderately conspicuous incremental lines 

 or smooth; posterior end slightly shorter, both ends evenly rounded, base 

 arcuate; hinge with a large pit for the resilium, left valve with the anterior 

 cardinal large and prominent, the hinge-plate thickened behind the pit, narrower 

 in the right valve. Alt. 5, Ion. 7, cliam. 2 mm. 



This species is represented by four somewhat worn valves in the National 

 Collection. They show no traces of pustulation, which may, however, have been 

 worn off. It recalls 5". constricta but is smaller, less inflated, and more com- 

 pact. 



Sportella pelex n. sp. 

 PLATE 44, FIGURE 10. 



Miocene of Petersburg, Virginia, Burns ; Cove Point, Maryland, Maryland 

 Geological Survey. 



Shell small, solid, compressed, inequilateral, the posterior side quite short 

 and blunt ; beaks low, surface sculptured with fine regular incremental lines, 

 of which a few at wide intervals are more conspicuous ; basal margin nearly 

 straight, anterior end produced, rounded, posterior bluntly rounded ; left valve 

 with a strong hinge, the anterior lamella obsolete, but the one behind it promi- 

 nent and strong, socket of the resilium deep, the hinge-plate above it obscurely 

 thickened, a narrow but distinct groove for the external ligament ; interior 

 polished, the adductor scars rather high up, the disk faintly radially striated, 

 the margin entire. Lon. 7.3, alt. 5.5, diam. 2 mm. 



This species has a good deal the shape of a small Mesodesina and is nearest 

 to 5". yorkensis, compared with which it is higher and more inequilateral and 

 with a more oblique anterior dorsal slope. 



Several other species of Sportella as yet undescribed appear in the collec- 

 tions of the Maryland State Geological Survey from the Miocene, among 

 which one from the Cove Point, Maryland, Miocene has received the manu- 

 script name of Sportella recessa from Mr. L. C. Glenn of the Survey. I have 

 included (Plate 45, Figure 13) an illustration of this species with the others. 



Genus ANISODONTA Deshayes. 



Eucharis Recluz, Journ. de Conchyl., i., p. 164, 1850. Type Corbula quadrata Hinds ; 



Fischer, op. cit., viii., p. 83, 1860; xxxiv., p. 193, 1886; not of Latreille, 1804. 

 Poromya Deshayes, An. s. Vert. has. Paris, i., p. 248, 1857 ; not of Forbes, 1844. 

 Anisodonta Desk, An. s. Vert. has. Paris, i., p. 542, 1858; Cat. Moll. Reunion, p. 15, 



1863; Cossmann, Cat. 111. has. Paris, i., p. 136, 1886; ii., p. 204, 1887. 



