THE CANADIAN ENTOMOLOGIST. 143 



Another thing, and a very important one, which has greatly influenced 

 me, in making so many families, is, that not only do the imagoes them- 

 selves seem to possess good morphological characters that justify this 

 separation, but that these are, in many instances, seemingly correlated 

 by excellent morphological characters possessed by the larvse, which 

 would seem to indicate many natural groups. 



My present views, respecting the arrangement of the series and 

 families recognized, are incorporated in the following tables : 



II. Sub-order Phytophaga. — Abdomen broadly sessile; larvte with legs. 



Anterior tibiae with one apical spur Series I. — Xylophaga, 



Anterior tibiae with two apical spurs Series II. — Phyllophaga. 



Series I. — Xylophaga. 



This series represents four distinct families, which may be separated 

 by the following characters : 



Metathorax fissured in the middle at apex 2 . 



Metathorax not fissured. 



Vertex tuberculate ; antennje inserted below the clypeus and eyes ; 

 front wings with two submarginal cells ; abdomen cylindrical or 



depressed ; ovipositor not exserted Family I., Oryssidse. 



2. Middle lobe of mesonotum attaining the scutellum and separated from 

 it by a transverse line ; abdomen cylindrical or depressed. 

 Prothorax large, subquadrate ; costal cell of front wings not 

 divided by a transverse nervure ; tip of abdomen ending in a 



triangular or lanceolate process Family II., Siricid^e. 



Prothorax conical ; costal cell of front wings divided by a trans- 

 verse nervure ; abdomen at tip normal... Family III., Xiphydriidre. 

 Middle lobe of mesonotum not attaining the scutellum; abdomen more 

 or less compressed Family IV., Cephidse. 



Series II. — Phyllophaga. 



This series I have separated into eleven distinct families, distin- 

 guished as follows : 



Prothorax emarginate behind ; middle lobe of mesonotum much 

 longer than broad, not separated from the scutellum by a deep 

 fovea ; costal vein usually strongly thickened or clavate towards 



apex ; costal cell without an intercostal vein 2. 



Prothorax subtruncate behind ; middle lobe of mesonotum not much 

 longer than broad, and separated from the scutellum by a deep 



