LYMNA4ID2 OF NORTH AMERICA. 63 
universally distributed over the greater part of North America north 
cf the 38° of north latitude. These are shown in the subjoined table: 
distributed throughout ten regions. 
stagnalis appressd....... 
GARCHUMLON. 54 os ko akoe dare distributed throughout eight regions. 
GOIMSS Acts cs selolawrennion roe distributed throughout eleven regions. 
RAQUDONG, Vesnccwmcin sen ae distributed throughout seven regions. 
BOWUSTFUS ce Be Roe eases distributed throughout eleven regions. 
Three species are universally distributed between the 30° and 50° 
of north latitude. 
NOU DON ho Poe Gc OPA 
humilis modicella........ 
distributed throughout seven regions. 
distributed throughout nine regions. 
DOAN STON eet teete SACRE OOO distributed throughout nine regions. 
A number of species are peculiar to certain regions to which they 
are at present restricted. These are shown in the following tables: 
CENTRAL AMERICAN REGION. 
attenuata. columella champtont. 
West INDIAN REGION. 
cubensis aspirans. 
francisca. 
CAROLINIAN REGION. 
humilis. neopalustris. 
CALIFORNIAN REGION. 
bulimoides. sonomaensis. gabbi. 
CoLUMBIAN REGION. 
occidentalis. hinkleyi. jacksonensis. 
apicina solida. montana. 
COLORADOAN REGION. 
hendersoni. 
GREAT BASIN REGION. 
utahensis. pilsbryt. 
Upper MISSISSIPPIAN REGION. 
palustris blatchleyt. danielsi. reflexa hemphilliana. 
CANADIAN REGION. 
stagnalis perampla. pallida. catascopium adamsi. 
cyclostoma. davisi. catascopium niagarensis. 
Owascoensis. Nason. emarginata ontariensis. 
petoskeyensis. qwoodrufi. contracta. 
palustris alpenensis. pilsbryana. 
Nova Scotian REGION. 
elodes shurtlefi. pscudopinguts. decollata. 
YUKONIAN REGION. 
perpolita. alaskensis. peterst. 
ALASKAN REGION. 
atkaensis. truncatula, 
GREENLANDIAN REGION. 
holbollit. 
