LYMN^ID^E 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 : 



stagnalis appressa distributed throughout ten regions. 



caperata distributed throughout eight regions. 



obrussa distributed throughout eleven regions. 



galbana distributed throughout seven regions. 



palustris distributed throughout eleven regions. 



Three species are universally distributed between the 30° and 50° 

 of north latitude. 



parva distributed throughout seven regions. 



humilis modicella distributed throughout nine regions. 



obrussa 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 championi. 



West Indian Region. 



francisca. cubensis aspirans. 



Carolinian Region. 



humilis. neopalustris. 



Californian Region. 



bulimoides. sonomaensis. gabbi. 



Columbian Region. 



occidentalis. hinkleyi. jacksonensis. 



apicina solida. montana. 



COLORADOAN REGION. 



hendersoni. 



Great Basin Region. 



utahensis. pilsbryi. 



Upper Mississippian Region. 



palustris blatchleyi. danielsi. reflexa hemphilhanu. 



Canadian Region. 



stagnalis pcrampla. pallida. catascopium adamsi. 



cyclostoma. davisi. catascopium niagarensis. 



owascoensis. nasoni. emarginata ontariensis. 



petoskeyensis. zvoodruM. contracta. 



palustris alpenensis. pilsbryana. 



Nova Scotian Region. 



elodes shurtleM. pscudopinguis. decollata. 



Yukonian Region. 



perpolita. alaskensis. petersi. 



Alaskan Region. 



atkaensis. truncatula. 



Greenlandian Region. 



holbollii. 



