Descriptions of British Diptera. 



205 



II. — Characters and Descriptions of the Dipterous Insects indige- 

 nous to Britain.* By James Duncan, M. W. S., &c. &c (Con- 

 tinued from p. 459.) 



Family BOMBYLIM:, Leach. 

 Antenna consisting of three joints, the third not ringed and sur- 

 mounted hy an articulated style : proboscis long and porrected hori- 

 zontally from the lower part of the face ; palpi consisting of a single 

 joint ; head much narrower than the thorax ; the latter very convex 

 above ; legs long and slender ; wings divaricating, and usually hav- 

 ing four posterior cells. 



The insects included in this family belong principally to the 

 southern parts of Europe and to Africa. Comparatively few, there- 

 fore, fall to be described by the British faunist, and these all ad- 

 mit of being referred to three genera, viz. Bombylius, Phthiria, and 

 Ploas. These may readily be distinguished from each other by the re- 

 lative length of the proboscis, and radical joints of the antennae : 



Proboscis longer than f 1st joint of antennae much longer than 2d, Bombylius. 

 the head and thorax, \ 1st & 2d joints of antennae short and equal, Phthiria. 

 Proboscis shorter than the head and thorax, - - Plcas. 



Genus BOMBYLIUS. 

 Antennae inserted close together, the third joint turned outwards; 



the radical joint pret- 

 ty long and cylindri- 

 cal, clothed with very 

 long hairs, second 

 joint cup-shaped, 

 likewise hairy, third 

 long and subfusiform, 

 nearly naked, atte- 

 nuated, surmounted 

 by a short oblique 

 style, which consists 

 of three joints, the 

 central one longest, (Fig. 1 :) labrum very long and spear-shaped, 

 somewhat dilateda little before the point: tongue very long, and ta- 



* As these descriptive notices are intended to embrace all the species recorded 

 as British, it forms part of our plan to publish an appendix at intervals, supplying 

 any accidental omission in the original papers, describing new species, and 

 adding new localities, the latter of which have been furnished in great numbers 

 through the attention of our correspondents. By following this method, we shall 

 be enabled to present the subject in as ample, and, we hope, as complete a form, 

 as its present progressive state admits of. 



