LYMNZIDA OF NORTH AMERICA. Ro 
seminis small, rounded, its duct one-fourth longer than the penis-sac; 
vagina rather long. 
_ The comparative measurements may be tabulated as follows :! 
- Prost. Penis-sac 
Penis. Penis-sac. Vas.def. duct. Rec.sem. Penisretr.  retr. Shell. 
2.00 3.00 7.00 5.00 4.00 2.00 1.50 14.90 
2.00 3.00 7.00 6.00 4.00 2.00 1.50 13.00 
2.00 3.00 7.00 6.00 4.00 3.00 2.00 14.00 
There is very little variation in the genitalia of caperata, the size 
and shape of the different organs being quite uniform. 
RANGE (Figure 19): From Quebec and Massachusetts west to 
California; Yukon Territory and James Bay south to Maryland, In- 
diana, Colorado and California. 
Caperata is a species of northern distribution, occupying portions 
of the Canadian, Hudsonian, Mackenzian, Yukonian, Columbian, 
Coloradoan, Californian, Great Basin, Upper Mississippian and Nova 
Scotian regions. Its center of distribution embraces a broad belt across 
the center of North America from about the 38th to the 52nd degree 
cf north latitude, the belt being, therefore, about fourteen degrees in 
width. Caperata is a characteristic species of the Upper Mississippi 
Valley, from whence it has migrated to other parts of the country. 
So far as the forests are concerned, it seems to extend only slightly 
into the deciduous area in the southeastern part of its range, but occu- 
pies a large part of the coniferous area, as well as of the plain and 
prairie areas.” It extends through the Hudsonian, Canadian and Tran- 
sition life zones. 
The range of caperata has been restricted by some conchologists 
to the country east of the Rocky Mountains, but the records from 
California, Utah and Washington are authentic and there is no doubt 
of the range of this species to the Pacific Coast. Further records are 
needed from the western states and especially from British America, 
where the records indicate a northwesterly range to Alaska. 
1Dissection No. 23907. Dissection made in July, from Joliet, Illinois, 
specimens. 
*There are several records of this species from Louisiana and Texas, but 
no specimens have been seen from any state south of Indiana and Colorado; 
these records are believed to have been founded on some forms of the cubensis 
group, possibly Galba bulimoides techella or Galba cubensis, both of which 
bear some resemblance to caperata. The references and localities are as 
follows: : 
Adams, Sh. Red Riv. Louis., p. 244, 1854. 
Singley, An. Rep. Geol. Surv. Texas., IV, p. 188, 1892; p. 318, 1898. 
Frierson, Nautilus, XIV, p. 68, 1900. 
The first locality is near Cache Creek, Oklahoma; the Texas localities are 
in Hardeman, Gillespin, Baylor, Reeves, Swisher, Cottle and Stonewall coun- 
ties; Frierson records a _ small species from the great raft in the Red River, 
doubtfully as caperata. The writer has not been able to secure specimens from 
these localities for the verification of the records. Call’s records from Cimarron 
River, Oklahoma, and from Elk Creek, Barber County, Kansas, need confirma- 
tion. We suspect these to have been based on a variety of bulimoides, 
