Vol. XXlii] ENTOMOLOGICAL NEWS. 123 



Gyronycha Csy. (Coleop., Staphylinidae), a critical 



study. 

 By A. FENYES, M.D., Pasadena, California. 



Amongst the nearctic Aleocharinae, Gyronycha Csy. can 

 be characterized as follows : 



Tarsi 4-4-4- j ointed ; antennae n-jointed; right mandible 

 dentate, left simple; maxillary palpi 4-jointed ; labial palpi 

 3-jointed ; ligula bifid ; genae entirely margined. Tarsal 

 claws abruptly bent behind the middle. 



Mesosternal process acute; mesocoxal cavities entirely 

 closed ; middle coxae contiguous. 



Male with prominences on the third and seventh tergites. 



The tarsi are unquestionably 4-4-4- jointed, although the 

 fourth joint of the third tarsal pair (at least) apparently is 

 divided by an obsolete (anchylosed) suture. The clearest 

 view of the tarsi can be obtained by observing them from 

 below, where no vestiture will interfere. If we would ac- 

 cept the presence of this suture as a true demarcational line 

 between two joints, then the seemingly 5th joint would be 

 very short in Gyronycha, a circumstance entirely at variance 

 with the generally observed fact that the last tarsal joint 

 of the hind legs is always long in the Aleocharinae (if I am 

 not mistaken), and longer than the penultimate joint. This 

 preponderance in length of the last tarsal joint is undoubt- 

 edly necessary to give a better leverage to the tarsal claws, 

 especially where the latter are so strongly modified as they 

 are in Gyronycha. 



The last joint of the maxillary palpi is remarkably short, 

 especially when compared with the penultimate joint. 



The ligula is undoubtedly divided, and not entire, in cer- 

 tain lights seemingly only emarginate at tip ; the lobes rather 

 broad and subtriangular. 



The infralateral carina of the head can easily escape no- 

 tice, and is in some specimens seemingly interrupted behind, 

 but always visible when the lower surface of the head is 

 freely displayed and viewed in proper light. This carina in 



