1922] 



Graham: Wing Venation of Coleoptera 



199 



proportion of the families of Coleoptera, for example, Bupres- 

 tid«, Tenebrionidae, Elateridae, Bostrychidas, Spondylidae, 

 Cistelidae, Melandryidas, Oedermeridas, Pythidse, Trogositidae, 

 Erotylidce, Colydidae, Mycetophagidae, Mordellidae, Meloidae, 

 and others. 



This group is characterized by the fading out of the fused 

 part of R3+4, leaving a straight vein between R2 and R4. The 



CURCUUONIDAE 



IT 



CURCUUONIDAE 



IP/DAE 



SCARABAEIDAE 



EZr SILPHIDAE 



EZZ7 STAPHVLINIDAE 



Fig. 5. 



various steps of this process are shown in species of Ceramby- 

 cid«, Chrysomelidse, Spondylidae, and Bostrychidae. The trans- 

 verse fold in this group cuts off the primary venation from the 

 apical area of the wing. 



We still have left a group of wings which have become so 

 specialized that the venation gives very little hint of possible 

 relationships and need not be discussed except to say that a 

 number of widely separated families are represented. (Fig. 5). 



