The Genus Gyrotoma ' 15 



farther up the Coosa. For example, at Butting Ram Shoals, half the pu- 

 milum are smooth. Color varies from sulphine-yellow to dark oHve. About 

 one shell in four lacks color bands. The prevailing formula is four bands, 

 the third from the top being smaller than the others. The aperture is ovate 

 to elliptical, white to yellowish-white. In Wetumpka shells the folds show 

 through as broad white bands in the aperture. The columella is rounded, 

 not wide, white to bluish-white. It is not nearly as stout as might be expect- 

 ed in a shell of this size. At the mouth of the fissure is a spot of white 

 callus. The outer lip is curved outward at the top and is slightly crenulate 

 in shells with folds. 



In juveniles the spire is smooth, conic, the whorls flat, the suture not 

 much impressed, the periphery angular. The fissure begins with the fifth 

 whorl. Embryo shells are of about 1^2 whorls, closely coiled and without 

 sculpture. 



The species occurs from Weduska Shoals to Wetumpka. The Weduska 

 Shoals specimens are a dwarf form, occurring in very small numbers. The 

 largest is 19 x 9 mm. The shell is delicate, shining, the upper whorls having 

 low plicae, the base bearing obscure folds. The fissure in these specimens 

 is straight to slightly oblique, 3 to 4 mm. in depth. The temptation has been 

 to allow them a distinctive name, but the form appears to correspond with 

 dwarf piimilum collected by Mr. Smith at Higgin's Ferry, The Bar and 

 Duncan's Riffle. 



A note upon one of Mr. Smith's labels for this species reads, "On rocks, 

 in very swift water, 1-3 feet deep." 



Hinkley (2, p. 41) makes pumiliini a synonym of excisum. An examina- 

 tion of the types of the two species compels me to disagree with him. 



Gyrotoma alahamensis (Lea) 

 PI. I, figs. 12 and 13 



Schizostoma Alabaincnsis Lea, Proc. Acad. Nat. Sci., Phila., XII, i860, p. 187; 

 Journ. Acad. Nat. Sci., Phila., V, n. s., 1862, p. 250, pi. 35, fig. 54 ; Obs. Gen. Union, IX, 

 1863, p. 72, pi. XXXV, fig. 54; Lewis, Amer. Journ. Conchol., V, 1869-70, p. 168; Tryon, 

 Monog. Strepom.. 1873. P- 367 ; Lewis. Fauna of Ala.. 1876, p. 22. 



Gyrotoma Alabamensis Lea, Binney, Check List, i860. No. 305; Brot, List, 1862, 

 p. 27; Paetel, Cat.. 1888, p. 361. 



Gyrotoma olivula cxcisa (Lea), Hannibal, Proc. Malacol. Soc, X. IQ12. p. 181. 



Melatoma babylonicum Lea, Reeve, Monog. Melatoma, i860, sp. 6. 



Description: Shell striate, elliptical, stout, yellowish-olive, imperforate; spire 

 obtusely conical; sutures very much impressed; whorls six, banded, rather inflated, 

 the last very large; fissure oblique and rather short; aperture rather large, ovate, banded 

 within and obtusely angular at the base; columella white, somewhat thickened above 

 and below; outer lip sharp and sinuate. 



Habitat: Alabama; B. W. Budd, M.D., and Dr. E. R. Showalter. 



Diameter, .50; length, .90 of an inch.— Lea. 



The description, "fissure oblique and rather short" so misled Mr. Smith 

 that when he found alahamensis he was compelled to believe that he had 

 come upon a new species. Examination of the type disclosed, however, 

 that the shells of Lea and Smith were the same. The fissure varies from 

 straight to oblique. Of 37 shells from The Bar, Chilton County, 16 had 



