190 TESTACEOUS MOLLUSCA. 



U. Splendidus. Lea. on U. 2, p. 70. t. 19. /. 61. Ellip- 

 tical, very inflated, tliickish, inequilateral, ventral edge somewhat 

 rounded ; beaks prominent, anterior slope with three indistinct 

 ribs ; umbonal slope carinated : cuticle yellowish covered with 

 numerous dark green rays, nacre rosy ; cardinal teeth somewhat 

 compressed, the lateral separate and lamellar. \^^..2^ — Geor- 

 gia in America. 



U. OcHRACEUS. Say. in Nic. Enc. Am. Cone. t. 2. f. 8. — 

 Conr. 3Ion. U. t. 17. ./• 2. — Symphonota O. Lea. on U. 1: 

 J). 69. Subovate, inequilateral, transversely wrinkled, inflated, 

 thin, connate before the ligament which is not concealed, not 

 winged ; beaks full and prominent, with several concentric undu- 

 lations : cuticle glossy, varying from yellow ochre to brown ochre, 

 with oblique rays which anteriorly are more numerous, nacre bluish 

 white and ochraceous ; cardinal and lateral teeth forming a curved 

 line. 1 y'o • • 2to • — Delaware. 



U. Cariosxjs. Say. Enc. Am. — Am. C. t. 3. f. 2. — Barnes. 

 — Lam. — U. Luteola. Conr. Ovate or oval, not very thick, 

 anteriorly longer, (and usually dilated) discs swelled, umbones 

 elevated ; cuticle olive brown, or greenish, usually rayed with 

 green, nacre bluish white, often white reddish rose or salmon ; 

 ligament elevated : cavity moderate. 2 j^^^ . . /^ . — N. America. 



U. Perovatus. Conr. N. F. W. p. 47. t. 2. f. 3.—SiL 

 Jour. 25. t. 1../". 3. Transverse, ovate, rather ventricose, thick 

 but thinner on the anterior side, which is longer attenuated and ob- 

 tusely subangulated above and below ; ventrally and posteriorly 

 rounded, beaks rather elevated, approximated and undulated : cuti- 

 cle olive, wrinkled on the margin, nacre white : cardinal teeth 

 erect and prominent, not very thick. 2. — R. Alabama. 



U. Altilis. Conr. N. F. W. S. p. 43. t. 2. /. 1. Transverse, 

 suboval, thin, inflated, beaks shghtly prominent and much dilated ; 

 anteriorly longer dilated and obtusely siibangulated, ventral edge 

 arcuated and entire, umbonal slope rounded, behind which is an 

 obscure radiating rib: cuticle blackish, rugose, oHvaceous over the 

 umbones and rayed with short vermicular lines on the anterior slope, 

 nacre whitish and irridescent ; cardinal teeth subpyramidal, erect, 

 the lateral distant. 2. — Alabama. 



U. MuLTiRADiATUS. Lea. on U. \.p. 48. t. 9./. 13.— U. Fas- 

 cioLus. Conr. Mon. U . t. 11.,/- 2. — U. Ligamentina. Desk. 

 Elliptical, transverse, inequilateral, ventricose, thin, anteriorly ob- 

 tuse, posteriorly and ventrally rounded ; beaks prominent and 

 slightly undulated, cuticle olive yellow covered with green rays, 

 nacre bluish white : cardinal teeth erect and double in both valves, 

 the lateral lamelliform and abrupt. I^l. . 2. — Ohio. 



U. Novi Eboraci. Lea. on U. 2. p. 104. t. 24./. 1 14. Ellip- 

 tical, somewhat compressed, inequilateral, thickish, posteriorly 



