300 Mr. O. Thomas on a new Species of 



The colour- variations of G. erosa range from light to dark, 

 from brightly to dull-coloured, the New- World examples, as 

 a rule, liaving paler secondaries than those from the Old 

 World ; but even this character is by no means constant, the 

 hind wings being sometimes almost white, sometimes golden 

 ochreous, sometimes again smoky grey with white-tipped 

 fringes ; the dark lines on the primaries never seem to vary, 

 only the ground -colouring, and this varies to an extraordinary 

 degree ; so that from tlie same locality and collection one may 

 receive specimens having these wings of a nearly uniform 

 golden ochreous tint, or divided into two nearly equal light 

 and dark areas, always, hovs'cver, showing the same silvery 

 spot in the cell and dark (sometimes nearly black) transverse 

 irregular lines. 



Cosmophila erosa is the oidy species at present known to 

 me which exhibits tliis abnormal variability of antennal 

 structure, unless it should turn out that I was correct in 

 referring the Indian specimens of Bomhycia (since named by 

 Mr. Hampson B. lyersimilis) to B. viminalis. This is just 

 possible, but, judging from the constancy of our European 

 examples in this particular, not probable. 



Xhe fact nevertheless that any one species of moth is 

 capable of such marvellous inconstancy in the structure of tlie 

 male antennee seems quite to justify Mr. Hampson in re- 

 garding peculiarities in these organs as of secondary import- 

 ance when confined to one sex, and should make all lepido- 

 pterists liesitate to use them alone for distinguishing new 

 genera. 



XXXIX. — Description of anew Species o/' Vespertilio /rom 

 China. By Oldfield Thomas. 



Among a collection of small mammals from Foochow, South 

 China, presented to the National Museum by Mr. C. B. 

 liickett, occur two specimens, one in spirit and the other a 

 skin, of a very striking new species of bat, which may be 

 termed 



Vespertilio {Leuconoe) Bicketti, sp. n. 



General Characters. — Size large. Fur short. Feet and 

 claws enormously developed. 



Detailed Characters. — Fur soft, close and velvety. Muzzle 

 well-clothed, set with bristly whiskers, very much as in 

 F. mystacinus. Hind legs, both above and below, clothed to 



