LARVAL FORMS OF COLEOPTERA 



Adepliaga. This conception, however, is based on the knowl- 

 edge of the matnre larvae of only two genera, namely, Paussus (rep- 

 resented by three species) and Pleuroptenis (one species), and may 

 be altered by the eventual discovery of the earlier instars and of 

 the larvae of the more primitive genera. 



Family 



The series consists of a single family Paussidae (pi. 7 I-M) 



E. STAPHYLINOIDEA 



The series contains several fairly distinct associations of families 

 or subfamilies. Two of these are outstanding, namely, the leptinid 

 association containing very primitive larvae, and the staphylinine 

 association wdth greatly mutated and advanced larval types. To 

 the leptinid association belong the Limnebiidae, Leptinidae, Aniso- 

 tomidae, and Ptiliidae ; to the staphylinine association the very 

 specialized subfamilies Staphylininae, Thinopininae, and Paede- 

 rinae. The four families which constitute the association of primi- 

 tive larvae have been placed differently in the classification of the 

 imagines: The Limnebiidae, with genera Lim.nehins, Ochfhehius, 

 and Hydraena, were placed in the beginning of the Hj'drophiloidea 

 (auct.) ; the Anisotomidae, with subfamilies Cholevinae (auct.) 

 and Anisotominae (auct.), and the Leptinidae were included in the 

 beginning of the Staphylinoidea (auct.) ; the Ptiliidae at the 

 end of this latter series. The Hydroscaphidae are closely related to 

 the Limnebiidae. 



From the four primitive staphylinoid families are directly de- 

 rived the Scaphidiidae. the Platypsyllidae, and the Silphidae ; the 

 latter merely including NecropJiorus, Silpha, and the few other 

 genera usually listed as "Silphini." The entire family Staphy- 

 liuidae, as here conceived, consists of a complex of many subfami- 

 lies linked together into one large unit. 



There is a gradual transition from the Oxytelinae, which repre- 

 sents the nearest approach to the Silphidae, into the Paederinae, 

 which is the most specialized group of all the Staphylinidae. The 

 Pselaphidae and Scydmaenidae are here regarded as families 

 branched off from the Staphylinidae much in the same w^ay as the 

 Hydroscaphidae are branched off from the Limnebiidae, and the 

 Platypsyllidae from the Silphidae or Scaphidiidae. The larvae of 

 the small families Brathinidae, Clambidae, Clavigeridae, Sphaeri- 

 idae, and Sphaeritidae are either completely unknown or are at least 

 not present in the United States National ]\Iuseum. The Histeridae 



25 



