419 



NOTES ON BATS. 



ARTHUR WHITAKER, 

 Worsbrough Dale, Darnsley. 



(plate XVII.). 



Ix ' The Annual Report of the Yorkshire NaturaUsts' Union ' 

 for 1909*, mention was made of a ' brood of young Pipistrelles,' 

 taken in the Northallerton district. The phrase is a somewhat 

 misleading one, seeming to imply that the Pipistrelle produces 

 several young ones at a birth, and as attention was drawn to 

 this, and a query raised about it, in ' Nature,' (February 1910). 

 a fuller account of the incident referred to may be desirable. 



On July 2oth, 1909, ]\Ir. Denison Roebuck sent me some 

 bats which he had received from Mr. J. F. Musham, of Selby, 

 whose cousin had captured them in a farmhouse at Alne, in 

 the Northallerton district. 



Upon examination I found the specimens, six in number, 

 consisted of two adult female Pipistrelles (P. pipistrelliis), 

 both of which had evidently, from the condition of the breasts, 

 been suckling young ; two largish young bats of the same 

 species, nearly equal in size, and apparently, judging by the 

 growth of hair on back, head and chin, etc., of about the same 

 age. Previous experience of the young of this species led me 

 to judge the age of these two juveniles at fourteen or fifteen 

 days. The remaining two specimens were baby bats, and. 

 like the pair last described, apparently of about the same age, 

 which in their case, however, would not be more than eight 

 or nine days. 



It might naturally be assumed that these six bats com- 

 prised two families, each consisting of mother and twins. 

 I wrote to Mr. Musham, hoping to obtain further information. 

 I had especial interest in the matter, having had previous 

 experience, at various times, of the birth of thirteen young 

 bats (six being Pipistrelles), and in all these cases a single 

 young one only had been produced. 



Mr. ^lusham very kindly gave me the following information 

 as to the capture of the specimens : — On the evening of July 

 i8th, his cousin had retired to bed with his window left partly 

 open at the top. After about half an hour he was disturbed 

 by squeaking, and saw the two adult bats flying wildly round 



* ' The Naturalist,' lyio, p. 46 

 igio Dec. i. 



