046 



ZOOLOG Y— MOLLUSC A. 



Oregon and California only. My friend Mr. Gr. W. Try on considers the 

 presence of it in Utah as a valuable fact — indicating a much greater dis- 

 tribution than was formerly known. 



No. 



Locality. 



Date. 



Collector. 





(?) 



Shores of Lake Sevier, Utah 



Sept., 1S72 



G. K. Gilbert. 



Fam. planorbidae. 



Genus PLANORBIS, Guettard. 

 Subgenus Helisoma, Swainson. 

 PLANORBIS TRIVOLVIS, Say. 



Planorbis trivolvis, Say, Nicb. Encycl., 1817-19, pi. ii, f. 2. — Id., Am. Conch., pt. vi, 

 1834, pi. liv, f. 2.—LL, Binnev's ed., 44, pi. Ixx, f. 2; pi. liv, f. 2.— DeKay, 

 N. Y. Moll., 1S43, pi. iv, f. 59 a, /».— Gould, Invert. Mass., 1841, 201, f. 131.— 

 IIald., Mon., 1844, 13, pi. ii, tigs. 4-7.— Adams, Verm. Moll., 1842, 154.— 

 Kustkr, Chemnitz, ed. 2, 53, pi. v, tigs. 4-6 ; pi. vi, figs. 1-6, 20-25. — 

 Potiez & Miciiaud, Gal. des Moll., i, 214, pi. xxi, tigs. 19-21. — Anon., 

 Can. Nat., ii, 1857, 202, f. — .— Binney, Land & Fresh Water Shells N. A., 

 pt, ii, 1865, 116.— Roberts, U. S. Geol. Surv. Terr., 1870,468. 



Bulla fluviatilis, Say, Jour. Acad. Nat. Sci. Phila., ii, 178. — Say, Conch., Binuey's 

 ed., 71. 



Planorbis regularis, Lea, Trans. Am. Phil. Soc. Phila., ix, 6. — Id., ib., Proa, ii, 1841, 

 32.— Id., ib., Obs., iv, 6. 



Planorbis megastoma, DeKay, N. Y. Moll., 1843, 61, pi. iv, figs. 60, 61. 



Physa planorbula, DeKay, N. Y r . Moll., 1843, 76, pi. v, f. 83. 



Planorbis corpulentus, DeKay, N. Y. Moll., 1843, 64, pi. xiii, f. 185.— Whittemore, 

 Am. Jour. Sci. & Arts [1], xxxviii, 193. 



? Planorbis proboscidcus, Potiez & MiCHAUD, Gal. des Moll., i, 1838, 213, pi. xxv, figs. 

 13-15. 



Planorbis maerostomus, Whiteaves, Can. Nat., viii, 1863, 113, f. — . 



Planorbis trivolvis var.fallax, IIald., Moil, 1844, pi. iii, tigs. 1-3. 



Planorbis lentus, Gould, Invert., 1841, 202, f. 132. 



Helix trivolvis, Eaton, Zool. Text Book, 1826, 194. 



Cochlea trium-orbum, Lister, Conch., pi. cxl, f. 46. — Petiver, Gazophyl., pi. evi, f. 16. 



A very common species, being found everywhere throughout the 

 United States and Canada. In but one locality in Utah was it found liv- 

 ing, a ]■/., the ditches near Salt Lake City. 



At Panquitch Lake, Southern Utah, immense numbers of these shells 



