Dorothy J. Jackson 107 



Sides and under-surface. A broad stripe of large pale scales extends 

 along the sides of the thoracic segments commencing behind the eyes. 

 The scales on the posterior portion of this band and also those on the 

 ventral surface of the thorax are plumate in structure. Abdominal 

 sternites covered with long whitish fiat setae and a few plumate scales. 



Legs. Femora black with pale flat setae and a few scales; tibiae and 

 tarsi hght red with similar setae. 



Antennae. Light ferruginous, with pale setae, club darker. 



External Sexual Differences. 



The posterior abdominal segments differ in structure according to the 

 sex as in Siiona lineata. 



Species liable to he confused with S. sulcifrons and characters 

 which distinguish them. 



S. suturalis Steph. Eyes depressed and not projecting dorsally from 

 the level of the forehead. 



S. lineata L. Forehead, though with central furrow, quite flat between 

 the eyes. 



S. humeralis Steph., S. puncticollis Steph., S. flavescens Marsh and 

 S. cylindricollis Fahraeus. Anterior coxal cavities not reaching presternal 

 Hne. 



S. sulcifrons is not hkely to be confused with the bristle-bearing 

 species of Sitona. 



Wings o/S. sulcifrons. (Plate III, Figs. 4 and 5.) 



Specimens of sulcifrons collected from various parts of England and 

 Scotland have proved on examination to have brachypterous wings 

 (Fig. 5). These, however, are totally different in shape to those of 

 S. hispidula. They are of nearly equal breadth throughout and are evenly 

 rounded at the apex. They measure from 1-28 mm. long by 0-38 mm. 

 broad to 1-44 mm. long by 0-49 mm. broad. The wings show even less 

 trace of venation than those of S. hispidula, only a small portion of the 

 costal and sub-costal nervures at the base of the wing being discernible. 

 The wings are extremely deUcate and often to be found folded irregularly 

 into a narrow strip beneath the elytra. 



A curious variation in the shape of the wings has been observed in 

 a specimen collected at Invershin, Sutherland. In this (Fig. 4), the wing 

 is very long and narrow, measuring 1-6 mm. long by 0-34 mm. broad 

 and is narrowed towards the apex. 



