102 JOHN HAMILTON, M. D. 



76. A. arcticus Pai/k., reticHlntiis Kirby, var. sibirlcus Sahib. 



Taken at 6.3^ north latitude (Kirby), Labrador (LeConte), northern 

 Europe to 69° in Finland. Arctic Siberia (the Dudinka). T. v, 

 422 ; Sh., 526 ; Heyden, 56. 



77. A. nigroxneus Er., Erichsoni Harold, lutosus Cr. (T. x, 279). 

 California, Kan.sas, Slave Lake, Lake Superior, Canada, Hudson 



Bay, central and northern Europe. Siberia (the islands and afflu- 

 ents of the Jenisei). T. v. 419 ; Sh., 529 ; Heyden, 56. 



78. A. tristis Aube, var. diihius Mann., f atratus Manu. 



Occurs in New Mexico (Snoiv) ; Colorado {Schwarz) ; Lake Tahoe, 

 California; Alaska; Arctic Siberia (the Dudinka). T. iv, 422; 

 Sh,, 531 ; Heyden. " This species varies a good deal in color," 

 Sharp. 



79. Rhantus notatus Fab., sericans Sharp (T. x, 279), sutnralis Lac, roridus 

 Mull. 



This species has been found in Kansas (Suow, LeConte), Montana 

 {LeConte), British Columbia. Europe. Western Siberia Pr. 

 1866, 366 ; Sh., 619 ; Heyden, 57 ; Nord., 22. 



80. R. bistriatus Berg., sutiirellus Harr. 



This species occurs in Massachusetts, Illinois, Kansas, at Lake 

 Superior, Slave Lake, Hudson Bay. Central and northern Europe. 

 E. and W. Siberia. T. iv, 409 ; Sharp, 620 ; Heyden, 57 (sutnrellm 

 Harris). Adspersus Fab. is not a synonym of bistriatus Berg. 

 Sharp. 



Some other American and Eastern forms if not identical seem 

 very close, viz., sinuatus Lee. and Grapjii Gyll. scarcely differ, except 

 that the latter is a little larger (Sh. 617), 



81. Colymbetes Paykulli Er. 



No reference to this species has been observed in our literature. 

 Dr. Sharp (625) gives as its habitat " western North America," 

 north Germany ; Sweden ; Finland to 68° 30' ; Arctic Siberia 

 (Fadjanowsk). " Excessively near seminiger Lee, incequalis Horn ;" 

 Horn in litt. Saskatchewan River, B. C. Susanville, California. 



C. obscuratus Mann, is possibly identical, the chief difference being 

 that the transverse striolie of the elytra are somewhat finer and 

 denser (comparison by Mannerheim, 1853), quite a secondary 

 character. 



82. C. Thomsoni Sharp. 



Lapland. Iceland (? Greenland). Sh., 628. 



