THE NOCTULE, OR GREAT BAT 75 



the hind claws, and the head is bent under the body, whilst the 

 mouth is employed in active investigation amongst the fur of the 

 under surface. These bats when fully awake usually begin to 

 crawl over one another, a process which generally evokes a 

 stridulous chirping cry from the individuals which compose the 

 lower strata of the cluster." 



Although the sexes fly together, the extent of their inter- 

 mingling in their places of sleep and hibernation has often 

 formed the subject of discussion. Gurney,^ working in Norfolk, 

 believed that when the females have young they are found in 

 separate colonies, which are larger than those of the males. This 

 opinion coincides with that formed by Leisler many years before 

 in Germany, as well as with the more recent work of Messrs 

 R. RoUinat and E. L. Trouessart.^ It is also supported by the 

 recently recorded observations of Mr Booth, showing that both 

 sexes frequented the same den in about equal numbers until the 

 colony broke up for the summer in June and July, which is 

 about the time that the young are usually born. It is in agree- 

 ment with the known published records of the finding of both 

 sexes together, as by Mr Harting in February, by Daniell, 

 Mr Oldham, and Mr F. Norgate in May, and by Gurney and 

 Mr Whitaker in September.* In the latter case, a small colony 

 was found on the 2nd of the month, and on the 5th contained 

 seven adult females and one male, which may be supposed to 

 have resumed companionship after the young had been reared. 

 Exceptional cases evidently occur, as when Mr Whitaker* 

 met with fourteen individuals on 28th June, of which eleven 

 were males, one a pregnant female, and one a young male 

 aged about ten to fourteen days, and the mother of which was 

 presumably a bat which effected its escape. 



There is no evidence on one important point from British 

 observations, but it may be presumed that, as shown to be the 

 case in continental Europe, the true breeding season is in 

 September, when the bats, having reared their young, are in 

 winter quarters awaiting the period of hibernation. The com- 

 mencement of gestation is, however, probably delayed until the 

 awakening of the animals in spring.^ 



' Zoologist, 1887, 170. 2 Supra, p. 32. = Naturalist, 1905, 325-330. 



* In MSS. ^ Supra, p. 33. 



