NOKTII OF MEXICO. 



345 



TENEBRIO, Linn. 

 Tenebrio, Linn., Syst. Nat. Ed. VI; Neatns, Lee, Col. N. A., p. 2:!:!. 



The characters of this genus are too well known, to need special comment. 

 Our species are four in number, and may be distinguished as follows : 

 Trochantin of middle coxse very distinct. 



Surface dull, opaque. o b s c u r u s . 



Surface more or less shining. 



Thorax broader than long. m o 1 i t o r . 



Thorax sub-quadrate. c a s t a n e u s . 



Trochantin of middle coxse small. tenebrioides. 



T. obscurus, Fab. El. 1, 146. 



Easily distinguished from our other species by its opaque surface. 



Length .58-.62 inch. 



Abundant in the Atlantic region, where it has been introduced -from Europe. 



T. molitor, Linn., Fab. El. 1, 145. 



Similar in form to the preceding. The thorax is, however, more transverse and the 



margin broaden- and more distinctly reflexed. 



Length .50-.65 inch. 



Abundant in the same; regions with dbscurus. Also introduced. 



T. castaneus, Knoch, Nene Beitr., 171; interstitialis, Say, J. Ac. 8, 2(50. 



Differs notably in form arid sculpture from the preceding species. The thorax is here 

 nearly square, truncate at base, and more distinctly em a rgin ate in front. The sides are 

 more broadly margined arid the margin more reflexed. The surface is more coarsely 

 punctured. The elytra arc narrower and more elongate, their surface more deeply 

 striate and the stria; more strongly punctured. 



Length .40 inch. 



Specimens have been found in every region of our country, though not abundant. 



T. tenebrioides, Beanv. (Helops) Ins., p. 181, pi; 80, fig. 1; badius, Say, (Tenebrio) Journ. Acad. Si, 256. 



Similar in form to molitor. The trochantin of the middle COX83 is very small, and in 

 some specimens scarcely visible. Length ,48-.52 inch. 



Abundant over our whole territory; specimens have occurred in California. 



BIUS, Muls. 

 Bius, Muls., Col. Prance; Latigenes, p. 866. 

 B, estriatUS, Leo., (Tenebrio) Ann. Lye. 5, 14!). 



Similar in form to the European tJioracicus, but shorter, and with a more distinctly 

 margined thorax, with less prominent hind angles. Length .22 inch. 



Rare. Specimens have been found in California, and at Fort Simpson, Brit. Amcr. 



AMEHT. rrni.oso. SOO. — VOL. XIV. — 8? 



