106 Weevils of the Genus Sitona 



Nature of Damage. 



Damage by Adult. The adults of Sitona sulcifrons feed upon the leaves 

 of clover in the same way as those of Sitona hispidula. As a rule, however, 

 the eaten areas are more regular than in that species and more or less 

 U-shaped. From July to October nearly every clover leaf in certain 

 fields of first and second year "seeds" in Ross-shire showed the charac- 

 teristic notches eaten by this species, but the damage was never sufficient 

 to check the growth of the plant. The adults could often be swept from 

 the clover in numbers in this locality and out-numbered those of any 

 other species of Sitona. In Kent, S. sulcifrons appears to be less generally 

 distributed, but was abundant in temporary clover lays on the Downs 

 at Wye, though rare at a lower elevation. 



Damage by larvae. The larvae appear to feed principally upon the 

 root nodules of the clover and they sometimes damage the small fibrous 

 roots which bear them. Unhke the larvae of S. hispidula they have never 

 been observed attacking the main root. The larvae occur in the soil to 

 a depth of about 2 inches. 



Description of Adult. 



Black, sparingly covered with copper coloured scales and flat setae 

 which are frequently abraded. Size 2-9 to 4-2 mm. 



Head. Eyes prominent projecting from the sides of the head and 

 with their dorsal edge higher than the level of the central furrow which 

 runs down the middle of the forehead to the rostrum. The forehead 

 between the eyes is not flat but gradually slopes downwards from the 

 eyes on each side to meet the central furrow. Punctuation and scales 

 very similar to pronotum. 



Pronotum. Broader than long, covered with fairly closely placed 

 punctures which, though comparatively large, are shallow. Sparingly 

 clothed with flat copper coloured or ochreous setae, resembling scales 

 but hair-hke in width, and with indications of lighter dorsal and sub- 

 dorsal lines composed of similar but more closely placed setae inter- 

 spersed with elongated scales of pale yellow or copper. Anterior coxal 

 cavities just reaching presternal line. 



Elytra. Rather broad and short. Punctured striae most conspicuous 

 anteriorly but becoming obsolete towards the apex. Individual punctures 

 comparatively large. Intervals with finely punctured dots. Sparingly 

 covered with elongated, usually copper coloured scales interspersed, 

 especially on the sides, with flat setae of the same colour. Pale yellow or 

 silvery scales occur in groups producing a variegated effect. 



