664 



FAMILY XXVIII. — TROGOSITIDiE. 



aa. Thorax nearly twice as broad as long, sides much rounded, hind angles 

 small, obtuse. 

 d. Elytra unicolorous without spots. 



e. Size larger, 10-11 mm. ; intervals of elytra subconvex, minutely 

 rugulose. 1274. Americana. 



ee. Size smaller, not over 8.5 mm. ; intervals of elytra nearly flat. 



/. Dark reddish-brown to piceous. 1275. laticollis. 



ff. Light reddish or brownish-yellow. 1276. obscura. 



del. Elytra each with an irregular shaped yellowish spot in front of mid- 

 dle. 1277. BIMACULATA. 



T. mauritanica Linn., blackish-piceous and easily known by 

 having the joints of antennae gradually increasing in width, is a 

 cosmopolitan species which has been taken near Cincinnati. (Fig. 

 246.) It is commonly known as the "cadelle." 



1271 (3838). Tenebroides corticalis Melsh., Proc. Phil. Acad. Nat. Sci., 



Elongate-oblong, sub con- 

 vex. Black or piceous, feebly 

 shining ; antennae and legs pic- 

 eous. Head and thorax coarse- 

 ly punctate, the latter nar- 

 rowed, with sides sinuate be- 

 hind the middle, margins re- 

 flexed, base subtruncate. Ely- 

 tra shallowly striate, the striae 

 f with rows of rather coarse, 



Fig. 247. a, larva; "c, its mandible; a, antenna; e, under side ol ' 

 head; /, the 2-horned anal plate; b, the beetle; h, its antenna; i, (Jeep oblong punctures ', inter- 

 mandible; g, labium and its palpi; j, one of the maxillse and its 



palpus. (After Riley.) vals nearly flat, slightly rugu- 



lose, each with two irregular rows of very minute, oblong, distant punc- 

 tures. Length 7.5-8 mm. (Eig. 247.) 



Southern half of State : scarce. April 18-October 10. 



1272 (3838b). Tenebroides dubia Melsh., Proc. Phil. Acad. Nat. Sci., II, 



1844, 110. 



Resembles corticalis but smaller. Thorax more quadrate, sides scarce- 

 ly at all rounded; punctures more sparsely placed and coarser; those of 

 intervals of elytra distinctly larger and in more regular rows. Length 

 5-6.5 mm. 



Throughout the State; frequent. February 14-November 8. 

 Occurs beneath bark and logs, where it hibernates. 



1273 (3839). Tenebroides nana Melsh., Proc. Phil. Acad. Nat. Sci., II, 



1844, 10. 



Elongate-oblong, subdepressed. Dark reddish or chestnut brown. Tho- 

 rax more depressed, slightly broader than long, sides moderately rounded 

 and feebly converging, but not sinuate behind the middle; punctures, as 



II, 1844, 109. 



