Ears oblong, nearly as long as the head, deeply notched on their external margins ; tragus half the length of the auricle, subulate, bending slightly inwards towards the tip: fur reddish gray above, ash-colour beneath.
Length of the head and body two inches; of the head eight lines; of the tail one inch five lines; of the ears six lines; of the tragus three lines; breadth of the ears three lines and three quarters; of the tragus at the base three quarters of a line; length of the fore-arm one inch four lines; of the thumb two lines and three quarters: extent of wing nine inches six lines.
Bearing some relation to the Pipistrelle in its physiognomy, but distinguished from that species by its somewhat superior size. Muzzle rather obtuse; head flattish; face hairy, but the hair on the nose and chin thinly scattered and longer than on the other parts; a moustache of soft longish hair on the upper lip, above which is a congeries of glands extending from the eyes to the nostrils: ears moderate, a little shorter than the head, oblong approaching triangular, rounded at the extremity, , the inner margin bending outwards, the outer one sinuate and rather deeply notched about half way down; tragus half the length of the auricle, linear approaching to subulate, nearly straight but having a slight bend inwards: thumb longer and stouter than in the Pipistrelle : hind feet remarkably large and strong, much more so than in either the Pipistrelle or the next species, the toes set with bristly hairs: inter-femoral moderately ample; the spur rather short: tail a little longer than the fore-arm, exserted for about one line. Fur long; the hair on the upper parts with the basal half dusky, the tips reddish brown, this last colour alone appearing externally; beneath black at the roots, ash-gray at the tips: ears and flying membrane dusky; under surface of the inter-femoral whitish.
Stated to have been found near Dover by M. A. Brongniart, and in Fifeshire by Dr Fleming. The description given above is from a specimen in my possession taken at Milton Park in Northamptonshire. It may possibly be distinct from the true V. emarginatus of the continental authors, but it appears to approach nearer to that species than to any other I am acquainted with. Mr Yarrell has also a specimen which was taken at Islington.