NO. 1205. S YNOPSrS OF THE XA 1. 1 D ESSIMPSOX. 769 



37. *REEVE,Conch. Icon., XVI, 1864, pi. v, fig. 20. * B. H. WRIGHT, Check 



List, 1888. 

 *Hargaron ( Unio) elliottii LEA, Syu., 1870, p. 29. 



Southern Georgia to Texas. 



tQUADRULA UNDULATA Barnes. 



* Unio undulatus BARNES, Am. Jl. Sci., VI, 1823, p. 120, pi. n. *HILDRETII, Am. 



Jl. Sci., XIV, 1828, p. 279. * HAXLEY, Test. Moll., 1842, p. 175; * Biv. Shells, 

 1843, p. 175, pi. xx, fig. 26.* CATLOW and REEVE, Conch. Norn., 1845, p. 

 65.* CHENU, Bib. Conch., 1st ser., Ill, 1845, p. 24, pi. v, figs. 1, la.* H. and 

 A. ADAMS, Gen. Rec. Moll., II, 1857, p. 495. * CHENU, Manual, 1859, II, p. 143, 

 fig. 704. *SOWERBY, Conch. Icon., XVI, 1868, pi. LXXVI, fig. 399. * CALK- 

 INS, Pr. Ottawa Acad. Sci., 1874, p. 45.* B. H. WRIGHT, Check List, 1888. 



* Margarita (Unio) undulatus LEA, Syn., 1836, p. 12; 1838, p. 14. 



*Margaron ( Unio) undulatus LEA, Syn., 1852, p. 20; 1870, p. 29. 



*Mya undulata EATON, Zool. Text-Book, 1826, p. 219. 



* Unio undulata VALENCIENNES, Rec. Obs. Zool. Anat., II, 1833, p. 229, pi. LI v, 



figs. 3, 3a, 36.* DESHAYES, Tr. Elem. Conch., 1839, p. 19, pi. xxx, figs. 8, 9. 

 *Quadrula undulata BAKER, Moll. Chicago, Pt. I, 1898, p. 82, pi. xxn, figs. 1, 2; 



XII, fig. 1. 



*Unio costatus SAY. Am. Conch., VI, 1834. * CONRAD, New F. W. Shells, 1834, 

 p. 68. *FERUSSAC, Guer. Mag., 1835, p. 27. * CONRAD, Monog., 11,1836, 

 p. 17, pi. vii. * KUSTER, Conch. Cab., 1852, p. 54, pi. XI, fig. 4. * REEVE, 

 Conch. Icon., XVI, 1864, pi. iv, fig. 16. 



*Plectomerus costatus CONRAD, Pr. Acad. N. Sci. Phila., VI, 1853, p. 260. 



*Unio j)licatu8 KUSTER, Conch. Cab., 1856, p. 137, pi. XL, fig. 3. * CHENU, 

 Manual, 1859, II, p. 143, fig. 706. 



*Unio atrocostatus SOWEUBY, Conch. Icon., XVI, 1868, pi. LXXVII, fig. 404. 



tQUADRULA UNDULATA var. LATECOSTATA Lea. - 



*Unio latecostatus LEA, Pr. Am. Phil. Soc., IV, 1845, p. 163 ; l *Tr. Am. Phil. 

 Soc., X, 1848, p. 68, pi. I, fig. 2 ; * Obs., IV, 1848, p. 42, pi. i, fig. 2.* KUSTER, 

 Conch. Cab., 1861, p. 251, pi. LXXXIV, fig. 4. * B. H. WRIGHT, Check List, 



*Margaron (Unio) laticostasus LEA, Syn., 1852, p. 21. 

 *Margaron ( Unio) laticostatus LEA, Syn., 1870, p. 31. 



*Unio laticostatus II. and A. ADAMS, Gen. Rec. Moll., II, 1857, p. 497. *P/KTEL, 

 Conch. Sam., Ill, 1890, p. 156. 



tQUADRULA UNDULATA var. PILSBRYI Marsh. 



* Unio pilsbryi MARSH, Nautilus, V, 1891, p. I. 2 *PILSBRY, Pr. Ac. N. Sci. Phila., 

 1892, p. 131, pi. vm, figs. 7, 8; * Nautilus, VII, 1893, pi. I, figs. 7, 8. 3 



1 More compressed and having finer, more delicate plications than the type. I 

 have traced it northward into Kansas, where it gradually assumes the ordinary form 

 of undulata. Occasional specimens are found in the Northern States which agree 

 very well with the typical lalecostata. 



2 I feel quite sure that this is only a peculiar variety of undulata. 



3 A peculiar shell belonging to Mr. J. H. Ferriss, of Joliet, Illinois, from Lake Win- 

 nipeg, has been examined by the writer. It has unusually strong growth lines and 

 is quite full in the ventral region, and has only the very faintest vestiges of plica- 

 tions below the lower part of the posterior ridge. I regard it as a smooth form of 

 Q. undulata, and if any considerable number of such specimens were found it might 

 be worthy of a varietal name. 



Proc. N. M. vol. xxii 49 



