NATURAL SCIENCES OF PHILADELPHIA. 359 



clothed with prostrate cinereous hair ; the thorax is more than one-half wider 

 than long, and considerably rounded at the sides, which are distinctly ser- 

 rate ; the antennae are black, with the third and fourth joints triangular, but 

 a little narrower than the fifth. The thighs are piceous, the tibiae and tarsi 

 paler. I should have referred this species to L i s t r u s, but for the fact tiiat 

 the appendage of the outer claws is as long as the claw itself, and entirely 

 connate, while that 'of the inner claw is about two-thirds as long, obtusely 

 rounded at tip, leaving the tip of the claw free. 



ALLONYX Lee. 



This genus agrees in character with Dolichosoma, except that the outer 

 claw is slender, with a feeble dentiform dilatation at base: the inner claw is 

 furnished with a broad obtusely rounded appendage connate almost to 

 the point of the claw* in the first species, and entirely masking the point in 

 the second. The mandibles are acute at tip. The antennae are shorter than 

 the head and thorax, feebly serrate, with the third and fourth joints nearly 

 cylindrical, and narrower than the fifth. The thorax is marked with a deeply 

 impressed transverse line near the base, which bends forward each side, and 

 extends to the apex, forming thus a longitudinal furrow, about one-third dis- 

 tance from the lateral margin. The sixth ventral segment is prominent and 

 impressed in both of the specimens before me. 



1. A. sculptilis Lee, Class. Col. North America, 193. Dasyles sculptilis 

 Lee, Proc. Acad. N#. Sci. Philada., 1859, 75. 



One specimen. Fort Tejon, California ; Mr. Xantus. The pubescence is 

 very fine and sparse; the thorax transverse, not narrowed in front, sides 

 rounded in front, sinuate behind, with the hind angles rectangular and pro- 

 minent. The elytra are nearly parallel on the sides, and the tip is broadly 

 rufo-testaceous ; the antennae, palpi aud legs are rufo-testaceous, the hind 

 femora blackish at tip; the palpi are also blackish at tip ; the inner claw is 

 free at tip. Somewhat resembles a small Trogosita in appearance. 



2. A. plumbeus, elongatus, plumbeo-niger, opacus, pube cinerea 

 longa depressa dense vestitus, capite piano punctulato, sulculo supraoculari 

 brevi insculpto ; thorace capite paulo latiore, latitudine vix breviore, a basi 

 antrorsum subangustato, apice truncato, lateribus subsinuatis, basi medio 

 truncata, utrinque oblique siuuata, angulis posticis rectis, alutaceoet punctu- 

 lato, linea profunda utrinque versus latera insculpto; elytris postice paulo 

 dilatatis, confertim punctulatis, pone basin oblique profunde impressis ; labro, 

 antennarum mandibularumque basi, pedibusque ferrugineis, palpis totis ni- 

 gris ; ungue interno apice baud libero. Long. -16. 



One specimen from Colorado, given me by Dr. S. Lewis. Quite different in 

 appearance from the preceding. It is possible that dissection would indicate 

 a relationship between this genus and Danacea of the other continent; 

 but the want of sufficient material prevents me from making the investiga- 

 tion. 



DASYTES Fabr. 



In this genus are to be included the following species, which, although 

 differing in appearance, agree in having the tarsal claws similar in form, 

 acute at tip, and armed with a basal dilatation, or a rounded lobe shorter 

 than the claw itself. The sixth ventral segment is prominent in both sexes. 

 Our species may be arranged as follows: 

 Thorax with a deeply impressed lateral line. 



Basal dilatation two-thirds as long as the claws 1. hudsonicus. 



Basal dilatation one-half as long as the claws 2. b r ev i u s c u 1 us. 



* By a ty|> graphical error in the table of genera (Class. Col. N. Am., 193) tlie appendage of the 

 claw is described as " narrow, and free almost to tlie base." The line defining A 11 o n y x should 

 not have been indented. 



1866.] 



