196 SYSTEMATIC PALEOXTOLOGY 



and lias fainter sculpture. It is much more like the variety figured by 

 Harris. 



Length, 4 mm.; width, 2.5 mm. 



Occurrence. — ISTaxjemoy Fokmatiox. Woodstock. 



Collection. — Maryland Geological Survey. 



Family PARALLELODONTIDAE. 



Genus CUCULLAEA Lamarck. 



CrcuLLAEA GiGAXTEA Conrad. 



Plates LIT, LIII, LIV, LV. 



Cuadlaea qigmitea Conrad, 1830, Jour. Acad. Nat. Sci. Phila., vol. vi, p. 237, -p\. x, 



tig. 4. 

 Cucullaea onochela Roi^ers, 1839, Trans. Amer. Philos. Soc, vol. vi, p. 373, pi. 



xxviii, flg. 3. 

 Cucullaea transversa Rogers, 1839, Trans. Amer. Philos. Soc, vol. vi, p. 373, pi. 



xxix, fig. 1. 

 Cucullaea gig antea H. C. Lea, ISiS, Proc. Acad. Nat. Sci. Phila., vol. iv, jd. 98. 

 Cucullaea onochela H. C. Lea, 1848, Proc. Acad. Nat. Sci. Phila., vol. iv, p. 98. 

 Cucullaea transversa H. C. Lea, 1848, Proc. Acad. Nat. Sci. Phila., vol. iv, p. 98. 

 Cucullaea rogersiana Nyst, 1848, Tabl. Synopt. Arcacees, p. 63. 

 Latiarca gigantea Conrad, 1865, Amer. Jour. Conch., vol. i, p. 11. 

 Latiarca onochela Conrad, 1865. Amer. Jour. Conch., vol. 1, p. 11. 

 Latiarca transversa Conrad, 1865, Amer. Jour. Conch., vol. i, p. 11. 

 Latiarca gigantea Conrad, 1866, Smith. Misc. Coll. (300), p. 4. 

 Latiarca onochela Conrad, 1866, Smith. Misc. Coll. (300), p. 4. 

 Latiarca transversa Conrad, 1866, Smith. Misc. Coll. (200), p. 4. 

 Latiarca idonea Conrad, 1872, Proc. Acad. Nat. Sci. Phila., p. 58, pi. ii, flg. 1. 

 Area rogersi Heilprin, 1881, Proc. Acad. Nat. Sci. Phila., p. 449. 

 Cucullaea onochela Rogers, 1884, Geology of the Virginias, p. 669, pi. iii, flg. 3. 

 Cucullaea transversa Rogers, 1884, Geology of the Virginias, p. 670, pi. iv, rig. 1. 

 Area onochela Heilprin, 1884, Contrib. Tert. Geol. and Pal., p. 87. 

 Cucullaea transversa Harris, 1894, Amer. Jour. Sci., ser. iii, vol. xlvii, p. 303. 

 Cucullaea gigantea Clark, 1895, Johns Hopkins Univ. Circ, vol. xv, p. 5. 

 Cucullaea gigantea Clark, 1896, Bull. 141, U. S. Geol. Survey, p. 84, pi. xxx, xxxi, 



xxxii, xxxiii. 

 Cucullaea gigantea var. Harris, 1897, Bull. Amer. Pal. No. 9, p. 49, pi. viii, flgs. 



3a, 4. 

 • Cucullaea gigantea Dall, 1898, Trans. Wagner Free Inst. Sci., vol. iii, pt. iv, p. 603. 

 .Cucullaea transversa Dall, 1898, Trans. Wagner Free Inst. Sci., vol. iii, pt. iv, pp. 



60.3, 646. 



Description. — "Shell subtriaugular, obliquely cordate; very ventri- 

 cose, with numerous longitudinal sulci; anterior side flattened, produced 



