76 THE NATURAL HISTORY 



I should tell you that I have got an uncommon calculus cegogro- 

 pila, taken out of the stomach of a fat ox ; it is perfectly round, 

 and about the size of a large Seville orange ; such are, I think, 

 usually flat. 



LETTER XXXVI. 



TO THE SAME. 



Sept. 1771. 



DEAR SIR, 



THE summer through I have seen but two of that large species 

 of bat which I call vespertilio altivolans, 1 from it's manner of 

 feeding high in the air : I procured one of them, and found it 

 to be a male ; and made no doubt, as they accompanied together, 

 that the other was a female : but, happening in an evening or 

 two to procure the other likewise, I was somewhat disappointed, 

 when it appeared to be also of the same sex. This circumstance, 

 and the great scarcity of this sort, at least in these parts, occasions 

 some suspicions in my mind whether it is really a species, or 

 whether it may not be the male part of the more known species, 

 one of which may supply many females ; as is known to be the 

 case in sheep, and some other quadrupeds. But this doubt can 

 only be cleared by a farther examination, and some attention to 

 the sex, of more specimens : all that I know at present is, that 

 my two were amply furnished with the parts of generation much 

 resembling those of a boar. 



In the extent of their wings they measured fourteen inches 

 and an half; and four inches and an half from the nose to the 

 tip of the tail : their heads were large, their nostrils bilobated, 

 their shoulders broad and muscular ; and their whole bodies 

 fleshy and plump. Nothing could be more sleek and soft than 

 their fur, which was of a bright chestnut colour ; their maws 

 were full of food, but so macerated that the quality could not be 

 distinguished ; their livers, kidnies, and hearts, were large, and 

 their bowels covered with fat. They weighed each, when entire, 

 full one ounce and one drachm. Within the ear there was some- 



1 [See Letter XXII. to Pennant. White's Vespertilio altivolans is the noctule 

 ( Vesperugo noctula, Schreb.). White first discovered it in Britain, but it had been 

 previously found in France by Daubenton and Buffon. The noctule is widely 

 distributed throughout the southern counties, reaching as far north as Yorkshire.] 



