106 JOHN HAMILTON, M. D. 



PLATYPSYLLID^. 



104. Platypsyllus castoris Rits. 



The systematic position of this curious insect seems to be now 

 finally settled. " First discovered on the American beavers in the 

 Zool. Gardens at Amsterdam. It is now known to inhabit the 

 beavers of Texas, Nebraska, the Hudson Bay region, Alaska, and 

 those taken in France at the mouth of the Rhone {Horti).'" T. xv, 

 23-26 ; T. x, 114 and plate (LeConte). 



105. Leptinus testaceus 3IuU., americanus Lee, Pr. 1866, 367; T. s, 113; C. 

 77. 



" Inhabits with field mice and other small rodents." Taken at 

 Keokuk, Iowa, by Dr. Brendel ; Washington ( Ulke and Schwarz), 

 Philadelphia {Ryder). My frequent searchings for this species have 

 resulted negatively. It occurs in Sweden, Germany and France. 



SILPHID^. 



106 Necrophorus vespilloides Hbst., pyginxus, heies Kiiby, defodiens Mann., 

 conservator Walk., mortuornm Fab., poUinctor Lee. 



The individuals of this species vary greatly in color ornamentation. 

 It extends across the continent from Nova Scotia to Alaska (Canada, 

 ^Michigan, Lake Superior; var. polllnctor, from Washington and 

 Oregon ; has the antennae entirely black). Under the name mor- 

 taormn it inhabits east Siberia to Kamtschatka, and in Araurland. 

 Europe. Pr. 1866, 367 ; T. viii, 234 and 814 ; Col. Am. 126 ; Hey- 

 den, 87 ; Hey den, 1886. 



107. Silpha lapponica Hbst., caudata Say, tnberculata Germ., californica 

 Mann., granigera Cliev. 



This s[)ecies is widely distributed in northern and western America 

 (Labrador commonly, Packard). Hudson Bay region (Lee. Cat.). 

 Canada ; Green Mountains, Vermont ; New York, Michigan, Lake 

 Superior, Nevada, Idaho, Colorado, Kansas, Texas (El Paso), New 

 Mexico, California (San Diego), Oregon, Washington; Alaska. 

 Northern Europe. Arctic and boreal Siberia from Ochotsk to 

 Nikolaevsk at the mouth of the Amur. P. vi, 278 ; T. viii, 238 ; 

 Col. Am. 124 ; Heyden, 86. 



108. S. opaca Linn. 



This species has, occurred at Lake Mono, California (Horn), Hud- 

 sun Bay Territory, the borders of the McKenzie and Slave Rivers ; 



