84 General Notes. [Jan. 
Mesodon. In Carroll County I have gathered six species of 
this sub-genus, but not more than two in any of the other counties. 
Of albolabris I got many in Carroll County, most of them of a 
large size, though on the higher grounds a small variety was 
found, and also a variety named aleni by Professor Wetherby. In 
Garland County I got a couple of shells of somewhat smaller 
size than the largest from Carroll County, and darker color. Of 
exoleta I found a small size in Carroll County. For some time 
after the lip is fully formed the shell is thin, and has no parietal 
tooth, but it seeenards Ors and a rather heavy tooth ap- 
pears. In Washington nty found a single specimen, which 
was only 19-15 mm. P SS Of thyroides, the same statement 
in regard to thickness and parietal teeth as in the last is true. 
This species was originally described as of 22-1914 mm. diame- 
ters, but I have it from Indiana 28-23 mm., and from Ohio and 
Missouri nearly as large. From Carroll County the shells were 
22-19 mm., and these have been identified as bucculentus, though 
this is the ‘typical size of ¢hyroides. Two shells from Sebastian 
ounty were of the same size, and, though apparently mature, 
they had no parietal tooth. From Jackson County they were larger, 
being 24-20 mm., and from Benton County were the smallest I 
have yet seen,—18-15 mm,—one having a parietal tooth, and three 
Franklin and Garland Counties they were nearly as large, while 
from Benton they were only 15-13 mm. I found elevatus in 
Carroll and Jackson Counties, and c/ausus in Carroll only. 
Patula perspectiva Say. In abundance in Carroll County; a 
single one found in Benton Count 
Patula alternata Say. In Carroll County it does not differ 
much from the northern specimens, but in Washington and Gar- 
land Counties it is much heavier ribbed, and has darker spots. 
Stenotrema leati Ward. In Carroll, Benton, and Washington 
ties. 
Stenotrema labrosa Bld. In considerable abundance in Carroll 
County ; also found in Washington, Crawford, and Garland 
Triodopsis inflecta S In Carroll County, ‘of light color and 
II-10 mm. diameter. - Similar but darker colored ones from 
Benton, Washington, ‘and Franklin Counties. In Garland and 
Hot Springs Counties each I found one, 12-10 mm. diameters, 
but looking much larger on account of their height. From 
others from the same place are of the ordinary shape and o 
ates mm. diameters.. 
 Triodopsis appressa Say. From the bluffs of the White River, 
in Carroll moore these shells are thin and of a very light horn 
color, with A E E OR Te petila eren oil e 
