AMERICAN COLEOPTERA. 149 



Synopsis of the QUEDIINI of the United States. 



BY GEORGE H. HORN, M. D, 



The genera here included form, by the arrangement adopted by 

 Dr. Leconte (Classification p. 63), a portion of the larger tribe 

 Staphyliuini, which is characterized by the insertion of the antennae 

 at or near the anterior margin of the front, above the base of the 

 mandibles and near to the antero-superior margin of the eyes. 



The present subtribe differs from the others in having the lateral 

 margin of the thorax single, and the side of the head beneath with 

 a distinct infra-orbital ridge. 



The species are all slender, either fusiform or almost linear and in 

 this respect resemble the Bolitobius group of the Tachyporini, with 

 which they have several characters in common. 



Our genera may be arranged as follows : 



Tarsi four-jointed; mandibles prominent. 



Maxillary paljai long, slender; anterior tarsal claws larger than the others. 



Tanygnathus. 

 Tarsi five-jointed. 



Antennae geniculate, first joint elongate; anterior tarsal claws larger than 



the others Acylophorus. 



Antennfe straight, first joint not elongate; tarsal claws similar on all 

 the feet. 

 Palpi subulate. Prothorax beneath without post-eoxal process. 



Heterothops. 

 Palpi filiform. Prothorax with post-coxal process Qiietlius. 



Ern-t/porus jjuncticollis Erichs., has been rejected from the above 

 system as the prothoracic margin is double. It will therefore take 

 place in the genuine Staphylinini nearer Philonthus. 



TAMYGNATHUS Erichs. 



Head slightly prolonged before the eyes which are oval and moder- 

 ately prominent, infra-orbital ridge distinct. Antennae geniculate, 

 inserted at the sides of the front above the base of the mandibles. 

 Maxillary palpi elongate, filiform. Mandibles elongate, slender, acute 

 at tip and decussating. Tarsi four-jointed, claws very small on the 

 middle and posterior tarsi, much larger on the anterior. 



This genus had been placed by Erichson among the Tachyporini, 

 but has very properly been removed. The insertion of the antennae 

 is that of the present group. The posterior coxse although transverse 

 are hidden in their outer half by the metathorax and the metathoracic 



