29 LiGxiTic Stage 



strongly defined; lines of growth smaller and much finer than the 

 revolving lines, suture deeply impressed, outer lip expanded, 

 strongly nodular within, columella with three folds, aperture 

 pointed and canaliculate at base. 



"Height 12 mm., width 7 mm. 



"" Locality. — Gregg's landing; Alabama river, Alabama. ' ' 



Canceilaria graciloides var. bella, nov. van, I'l. 3, iv^. 10. 



"Charadterized by strong, rounded varices, as many as three on 

 the body whorl. Shell is smaller than the type. 

 "Height 10 mm., width 6 mm. 

 "Locality. — Gregg's landing, Alabama river, Alabama." 



Many specimens from this localit)' show that tlie variety could 

 more properly have been called the species, and that the specimen 

 called the type of the species could have been referred to a variety 

 of the same. In other words, var. bella isthe conunon, abundant, 

 well defined form, \\\\\\^ graciloides \s, very lare. 



Mr. Aldrich has very kindly furnished the figures herewith 

 given and has lent me the type specimens for study. On our 

 largest specimens the lines of growth at their intenseclion w'ith 

 the revolving bands or heavy lines form slight nodes or ttibercles. 



Localities. — Alabama: Gregg's landing; Bell's landing. 



Types and specimens figured. — i\ldrich's collection. 



Olivella mediavia, ri. 3, fi^. 12. 



Syn. /'. bombilis, var. Aid., Geol. Surv. Ala., Bull, i, p. 53, 1SS6. 

 O. gracilis Aid., Geol. Surv. Ala., Bull, i, p. 56, 1SS6. 

 O. mediavia Har., Bull. Am. Pal., vol. i., p. 194. pi. 17, i\^. 19. 



Harris' original description. — {Loe. cit.) 



Lignitic specimens are sometimes nearly twice the size of the 

 Midway prototypes. They do not as a rule show the geniculation 

 in the growth lines on the lower portion of the bod>' whorl so 

 l)lainly as do the Midway specimens. A labial callosity near the 

 posterior portion of the aperture is often quite evident. The ex- 

 tent to which the spire is callosed over varies considerably in 

 different specimens; generally there is an exceedingly narrow 

 band of shell .showing lines of growth ju.st below the suture. 



