340 



and the sharply-clefiued carina of the pronotum, will readily distinguisli 

 this species from its congeners. 



At the extreme apex of the occiput is a minute notch to fit over and 

 admit the carina of the pronotum. 



2. C. vuhierata. 



Corixa vulnerata, Uhler, Proc. Acad. Phila. 1861, 284. 



Inhabits Montana, Oregon, and Northern Illinois. Common in many 

 sections of the Northwestern Territories of the United States, and no 

 doubt yet to be discovered in British Columbia and Canada. 



3. C. inter rupta. 



Corixa interriqita, Say, Joiiru. Acad. Pbila. iv, 328, No. 1. 

 Corisa interrupta, Fieb. Species Generis Corisa, 27, No. 28. 



Inhabits California, Missouri, Illinois, New England, New York, 

 Maryland, and Minnesota. Said by Fieber to be found also in Mexico 

 and Brazil. 



It presents some variation in the depth of color, and in the distinctness 

 of the lines of the pronotum and hemelytra. 



4. C. decolor. 



Corixa decolor, Uhler, in Packard's Insects lubabitiog Salt-Water, Silliman's 

 Journal, Itll, 106. 



From Clear Lake, California ; collected by Professor Torrey. 



The soft and tender condition of the two specimens examined leaves 

 a doubt of their being in fully-matured condition. It is important to 

 have full series of these insects from the various kinds of lakes, ponds, 

 and streams, particularly from the alkaline ones, so that something may 

 be settled respecting the influence of such waters upon them. 



5. C. calva. 



Corixa calva, Say, Ileteropt. New Harmony, 38, No. 1 ; Fieb., Generis Corisa, 19, 

 No. 12. 



Inhabits Pennsylvania, Massachusetts, Canada. Texas, and Alaska 

 {teste Fieber). 



6. C. ctbdominaUs. 



Corixa aMominaVis, Say, Heteropt. New Harmony, 38, No. 2. 

 Corixa himaculata, Gaer., Iconograpbie Eegue Animal, 353. 



Inhabits Mexico, California, and Texas. 



7. G. prceusfa. 



Corixa prKusta, Fieb., Species Generis Corisa, 28, No. 30, tab. i, 17, figs. 1-18. 



Inhabits Sitka and Alaska. 



8. G. striata. , 



Corixa striaia, Kirby, Fauna Bor.-Amer. iv, 283, No. 1. 

 Notonecta striata, Linn., Fauna Suecicce, 904. 



Inhabits British America and Nebraska, and seems to extend aroun d 

 the world in the northern division of the north-temperate zone. 



9. G.fossarum. 



Corixa fossarum, Leacb, Linn. Trans, xii, 17, No. 4; idem, Fieb., 1. c, 32, No. £7 



Inhabits California and Northern Euroi)e. 



