NATURAL SCIENCES OF PHILADELPHIA. 291 



Sph. distortum, Pr. Ads. rec. gen. ii. 450. 1858. Is Sph. solidu- 

 1 u m , Pr. 



Sph. dubium, Say. Ads. rec. gen. ii. 450. 1858. Is Pisid. V i r g ini- 

 c u m , Bgt. 



Cycl. dubiosa, Say. Reeve's Conch. Nomen. 29. 1845. Is Pisid. Vir- 

 gin icum, Bgt. 



Cycl. duplicata, Pf. Moll. Germ. 230. 1821. Is Pisid. duplica- 

 t u m , Pf. 



Cycl. D u p o n t i a , Fer. Cat. 20. 1837. Is Cyrenella D u p o n t i a , Joan. 



24. Sph. eburneum, Anth. Ads. rec. gen. ii. 450. 1858. 



Cycl. ebumea, Anth. in Pr. Bost. Proc. iv. 279. 1852. 

 Hab. N. Anier. 



Cycl. edentula, Say. New Harm. Dissem. 2, 356. 1829. Is Sph. 

 striatinum, Lam. 



25. Sph. egregium, Gould, (non Say.) Ads. rec. gen. ii. 450. 1858. 



Cycl. egregia, Gl. Bost. Proc. 3, 292. 1850. 

 Hab. Oceanica. 



Sph. elegans, C. B., Ads. Ads. rec. gen. ii. 450. 1868. Is Sph. 

 rhonoboideum, Say. 



26. Sph. elevatum, Hald. Ads. rec. gen. ii. 450. 1858. 



Cycl. elevata, Hald. Ac. N. S. Phil. Proc. i. 53. 1841. DeKay, 224. 



1842. Pr. Bost. Proc. iv. 280. 1852. Bgt. Amen. i. p. 8. 1853. 

 Cycl. pallida, Charp. Mss. 1851. 

 Hab. N. Amer. 



Cycl. elongata, Sowb. Gosl. trans, n. ser. iv. 345, pi. 21, f. 9. 1836. 

 Is Cyrena elongata, Dkr. 



27. Sph. emarginatum, Pr. Ads. rec. gen. ii. 450. 1858. 



Cycl. emarginata, Pr. Bost. Proc. iv. 156. 1851. loc. sup. cit. iv. 283. 



1852. Jay. Cat. iv. ed. 466. 1852. Bgt. Amen. i. p. 8. 1853. 

 Hab. N. Amer. 



Cycl. erebea, d'Orb. Prod. 2, 223. 1850. Is Cyrena e re be a , Pr. 

 Cycl. Euphratica, Lamk. An. Mus. vii. 420. 1806. Encycl. pi. 



302, f. 2, pi. 302, f. 2. Is Corbicula fluminalis, Adams. 



28. Sph. faba, Miinster. 



Cycl. faba, Miinst. Goldf. Petr. 2, 232, pi. 147, f. 8, a, c. 1834-40. 

 Hab. Germ, (fossil.) 



29. Sph. f abalis, Pr. Ads. rec. gen. ii. 450. 1858. 



Cycl. fabalis, Pr. Bost. Proc. iv. 159. 1851. Jay. Cat. iv. ed. 465. 



1852. Bost. Proc. iv. 273. 1852. Bgt. Amen. i. p. 8. 1853. 

 Cycl. castanea, Pr. Bost. Proc. iv. 160. 1851. loc. sup. cit. iv. 273. 



1852. Bgt. Amen. i. p. 8. 1853. 

 Cysl. salculosa, Charp. MSS. 1851. 

 Sph. casianeum, Pr. Ads. rec. gen. ii. 450. 1858. 

 Hab. N. Amer. 

 Cycl. fasciata, Gldf. Petr. 2, 232, pi. 147, f. 10, a, b. 1834-40. Is 



Cyrena fasciata, Roemer. 

 Cycl. Faujasii, d'Orb. Prod. 3, 109. 1852. Is Cyrena Fauiasii, 

 Desh. 



30. Sph. ferrugineum, Kr. 



Cycl. ferruginea, Kr. Moll. S. Afr. 7, pi. i. f. 7. 1848. 



Pisid parasiticum, Parr. MSS. 



Musculium parasiticum, Ads. rec. gen. ii. 452. 1858. 



" ferrugineum, Kr. loc. sup. cit. ii. 451. 1S58. 

 Pisum parasiticum, Parr. loc. sup. cit. ii. 500. 1858. 



I860.] 



