82 THE ENTOMOLOGIST. 



NOTES ON THE WINGS OF COLEOPTERA. 



I. The British Species of Pterostichus. 



By D. Sharp, M.A., F.R.S. 



I have been for many years interested in the questions con- 

 nected with the flight of Coleoptera, which are very peculiar, 

 owing to the fact that the anterior wings are passive, so 

 that the posterior are entrusted with the chief part of aerial 

 locomotion. Some very curious points arise from this unusual 

 entomological condition, but they cannot be profitably discussed 

 till we have much more information on the subject. The frag- 

 ment I here offer is very small, but may be of some use. 



I have to thank several friends for assisting me with material, 

 in response to an appeal I made several years ago. Mr. Champion, 

 Mr. Donisthorpe, Dr. Perkins, Mr. W. E. Sharp, and Commander 

 Walker kindly responded to that appeal, and to their assistance 

 is largely due any value these notes may possess. 



I have used the arrangement and nomenclature of Fowler's 

 ' British Coleoptera.' 



1. P. (Poecilus) cupreus, L. — Fully winged. Wings 10-11 mm. 

 long and 4 mm. wide; elytra, 7|- mm. long. Six examined, all 

 very similar, and all from the South of England. 



2. P. (Poecilus) ccerulescens, L. — Fully winged, but the wings 

 comparatively small, 6f-7£ mm. long, and 2|-3 mm. wide; 

 elytra, 6f-7 mm. long. Three examples seen : one from Scot- 

 land — the larger individual— one from Sheppey, and one from 

 Wimbledon ; this last is the smaller, and the reduction in size 

 of the wings is very marked. Captured April 16th, 1864. 



P. cupreus and ccerulescens are very closely allied, and as 

 they are each variable, it is often difficult to distinguish them. 

 The smaller size of the wings and metathorax in carulescens 

 seems to be the most important distinction. The male charac- 

 ters of the two are very similar. 



3. P. (Poecilus) dimidiatus, 01. — Fully winged. One speci- 

 men examined. Wing, 11 mm. by 4 mm. 



4. P. (Poecilus) lepidus, Fabr. — Flightless. The vestigial 

 wings small. Four specimens examined : two from Glasgow, 

 August, 1864 ; two from Nethy Bridge, June, 1907 ; length 1J 

 to fully 2 mm. ; of elytra, 7|-8 mm. The size differs a little in 

 each specimen, and in each of the two pairs the female has the 

 more elongate wings. 



5. P. (Steropus) madidus, Fabr. — Flightless. The vestigial 

 wings minute, |-f mm. long, and about | mm. wide. Three 

 specimens examined. The vestigial wings are slightly different 

 in each. In this species the metanotum is very short, and the 

 elytra become soldered together at the suture when the insect is 



