AMERICAN ENTOMOLOGY. 99 



men robust, convex ; elytra entire, not divided at the suture, 

 carinate each side, and embracing the sides of the abdomen ; 

 tarsi alike in the sexes. 



Obs. This is a limited genus, consisting in the time of Fabri 

 cius, who constructed it, of only five species. As it now stands, 

 under the reforming hand of Latreille and Dejean, it is certainly 

 more rigidly natural. The latter author, in his " Species general 

 des Coleopteres," describes nine species, and observes, that they 

 are limited, in their geographical distribution, to Europe, Asiatic 

 Russia, and North America ; that although they are, strictly 

 speaking, Carabici, yet they have so much the habit of the 

 Hi tfromera, that Linne placed them in his genus Tenebrio. 



They are of a blackish color, glossed with a handsome metallic 

 tint, chiefly of a purplish cast. They inhabit beneath stones, 

 and under prostrate logs. 



The word Cychrus is derived from ~K."XP°c, the Greek name for 

 a bird. 



Cychrus viduus. — Specific character. Black ; elytra cupre- 

 ous-violaceous, polished, humeral edge, and lateral margins of the 

 thorax reflected, the latter contracted behind. 



Cychrus unicolor Knoch neue Beytriige, p. 187, tab. 8, fig. 1. 

 Nobis, Trans. Amer. Philos. Soc. vol. ii. new series, p. 71. 



Cychrus viduus Dejean, Spec. Gen. Coleop. vol. ii. p. 12, No. 9. 



Desc. Head black, with a slight blue tinge : antenme brown 

 at tip : thorax blackish-blue, disk a little convex, and with an 

 impressed line ; lateral margins reflected ; widest rather before 

 the middle, and narrowed behind ; posterior angles rounded : 

 elytra bright coppery-violaceous, or dark purplish, with numerous 

 strice, in which are dilated, confluent punctures ; beneath black. 



Ohs. Probably the largest species of the genus, and is by no 

 means common. The specimen from which the above description, 

 and the annexed figure were taken, was presented to me by Mr. 

 William Hyde of Philadelphia, who obtained it near the Susque- 

 hanna river. Two other specimens have since come into my 

 possession. 



This species was first described by Knoch, under the name of 

 unicolor; supposing it to be the same with that of Fabricius, 

 and on his authority, I retained the appellation in my " Descrip- 

 tions of the Carabici and Hydrocanthari ;" but after the publica- 



