GASTROCOPTA, NORTH AMERICA, WEST INDIES. 79 



slight crest behind the outer lip, and a somewhat longer lower 

 palatal plica. There is often no projection on the columellar 

 side of the angulo-parietal lamella. Also by the pale brown 

 color and the average larger size. In the original description 

 a specimen of the minimum size was selected as type, but in 

 the same lot the size is variable, from length 1.8, diam. 0.76 

 mm., to length 2.5, diam. 1 mm. All of the characters distin- 

 guishing hordeacella from pellucida vary so much that in 

 some individual cases, without a large series, there is little or 

 no difference ; but it is only the smallest individuals of any 

 lot of hordeacella. which could be taken for pellucida. The 

 status of the subspecies is rather uncertain, and possibly it 

 might be abandoned with advantage. 



There are specimens which show no crest, and the color, in 

 the East, is often as pale as pellucida. 



G. p. hordeacella varies far more than Antillean pellucida. 

 The length varies from 1.5 to 2.6 mm., whorls 4 to 5^, 

 among specimens picked from one lot. Mr. Vanatta remarks 

 (Nautilus, xxvi, p. 17) that in picking them over one has a 

 tendency to divide each lot into several grades, long, medium, 

 small and obese, but these intergrade through a small number 

 of shells of intermediate size. ' ' The long shells from Florida 

 have weak teeth and the short specimens have strong teeth, 

 while in Texas the converse is often the case." There is con- 

 siderable variation in the development of the buttress under 

 the columellar lamella, which is sometimes scarcely noticeable, 

 sometimes so thick as to appear as a subcolumellar tubercle. 

 See pi. 16, figs. 5, 10, 26. 



Florida and the Keys, Georgia Sea Islands north along the 

 coast to Cape May, New Jersey. Ft. Gibson, Oklahoma, and 

 Texas, west to Trinidad, southeastern Colorado, Jerome and 

 Mt. Trumbull, Arizona. Guajadami, Lower California (Nel- 

 son and Goldman). Victoria (S. N. Rhoads) and Tainpico, 

 Tamaulipas (Hinkley) ; near Valles, S. L. Potosi (Hinkley). 

 Type locality, New Braunfels, Texas. 



On the Atlantic coast, though it extends as far north as 

 Cape May, its extension inland seems to be very narrow, so 

 far as the data show. In the west it is generally diffused, 



