STREPTOSTYLA. 155 



de Conchyl. 1869, p. 33; Miss. Sci. Hex., Moll., i, p. 51, pi. 1, 

 f. 13, 130. 



"Near the preceding [8. sololensis], but of smaller size, 

 thinner, the suture not white, but of the same yellow color as 

 the rest of the shell. Owing to the kindness of M. A. More- 

 let, I have been enabled to compare directly his original speci- 

 mens of 8. meridana (fig. 96) with the type of 8. cobanensis 

 Tristr. (fig. 97), and with the figure of Fischer and Crosse's 

 8. cornea; Morelet's type is only a little smaller, compara- 

 tively more slender, and paler in color, without any marked 

 difference. The statement 'length 18 mm.' is a misprint for 

 13 mm., as shown by the specimens themselves" (Martens). 



The type of S. meridana has been figured by von Martens, 

 and copied on my plate, fig. 96. I give some additional fig- 

 ures, on a larger scale, of specimens in the collection made 

 by the Academy expedition : 



Fig. 93, Santa Ana, near Calcehtok, 11x4.5, aperture 7 mm. 



Fig. 94, Tekanto, 10x4, apert. 6.8 mm. Last whorl very 

 slowly descending; columellar fold weak, spire short. 



Fig. 95, Ticul, 10.25x4, apert. 6 mm. Last whorl more de- 

 scending, the spire longer, columellar fold strong. 



In all the lots there is a quite narrow, clear, subsutural 

 margin, and the outer lip arches strongly forward in the 

 middle. Variation in size and contour is considerable. It is 

 more slender than the allied species $. ventricosula and 8. 

 yucatanensis, which occur with it in northern Yucatan. 



25a. Var. colancnsis (Tristram). PI. 30, fig. 97. 



Larger, length 13 to 14, diam. 5.3 to 5, alt. aperture 7 to 8 

 mm., and a little wider (Marts.) Guatemala. 



26. S. SOLOLENSIS C. & F. Vol. I, p. 46. 



27. S. COSTARICENSIS Da Costa. PI. 29, fig. 82. 



Shell cylindric-oblong, thin, pellucid-corneous, spire short, 

 obtuse at the apex. Whorls 5 l / 2 , almost flattened-convex, 

 margined at the suture, smooth, polished. Columella short 

 and twisted. Aperture oblong, narrowly auriform, the outer 

 lip impressed in the middle, white at the edge. Length 19, 

 diam. 9, aperture 13x3.5 mm. (Da Costa). 



