COLEOPTERA — SCOLYTID^E. 93 



TiiiBE SCOLYTINA. 



Genus Scolytus. 



The genus Scolytiis confines its attacks exclusively to the broad- 

 leaved trees of the forest or fruit-trees of the orchard. 



The chief generic characteristics are : Knob of antennae large, larger 

 than the whip ; eyes longish and linear ; body smooth ; thorax much 

 darker than the elytra. 



Si/noiK^/K of the Sfxiclrf;. 



I. (1) Second ventral segment of abdomen without projection. Elytra 

 shining, thickly punctured ; third and fourth segment in both 

 sexes furnished with a small tubercle. Mother-gallery per- 

 pendicular. Lives in elm . . . Scolytus destructor. 



(2) Thorax very finely punctured, especially on the disc. Mother- 



gallery long and perpendicular. Generally in fruit - trees. 



S. pruni. 



(3) Thorax very finely punctured, especially on tlie disc. Mother- 



gallery short and horizontal ; very long larval galleries. Lives 

 in oak ...... S. intricatus. 



11. (4) Second ventral segment with a strong horizontal projection. 

 Perpendicular mother-gallery. Lives in elm, poplar, cherry, 

 plum, pear, and oak . . . . S. multisfriatus. 



Scolytus destructor (Oliv.) 

 Scolytus Geoffroyi, Goetz (EichhotF). 



II II (Judeich and Nitsche). 



Eccojitogaster scolytus, F, (Altum). 



This beetle chiefly confines its attacks to elm-trees, and is therefore 

 commonly known as the " elm bark beetle." It is a dreaded pest in 

 elm-growing districts, as for example in many parts of the south of 

 England and in the London parks. The perfect beetles appear about 

 the middle of June, and the female commences her boring operations 

 either in a newly felled trunk or an unhealthy tree. Previous to 

 making the burrow proper, she makes a sort of pseudo-track in a deep 

 furrow of the bark ; and as the male appears about this time, it is 



