286 BA TS 



belonging to the premolar series, is invariably characterized by its minute size. Then, 

 again, the ear has a characteristic elongated oval form, and its tragus is very narrow. 



The genus appears to be of unusually wide geographical distribution, and is 

 found throughout the temperate and tropical regions of both hemispheres. ' ' Most 

 of the species," writes Dr. Dobson, "appear to be dwellers in woods, some either 

 habitually or occasionally live in caves or under the roofs of houses. The position 

 of attachment of the wings to the hinder extremities, and the size of the foot, appear 

 to be connected with the nature of their dwelling-places, the inhabitants of caves 

 having larger feet more or less free from the membranes, while those living in woods 

 have much smaller feet inclosed in the wing membrane to the base of the toes." 

 The bats of this genus being of a more delicate organization than the species of 

 Vesperugo are less capable of withstanding the effects of cold, and have therefore a 

 less northerly range than the later. And in the countries where the bats of these 

 two genera hibernate, those belonging to the present genus are later in awakening 

 from their winter slumber than are the species of Vesperugo. 



Daubenton's bat belongs to a group of the genus characterized by the large size 

 of the feet, and also by the wing membrane rising, as a rule, from the shin bone or 

 the ankle, as well as by the middle of the free margin of the membrane between the 

 legs forming a very acute angle. Moreover, the tail has one or two joints projecting 

 beyond the edge of the membrane last mentioned, and the spur arising from the ankle 

 to support the same is of very great length. The wing membrane extends below 

 the ankle to the metatarsus ; and the ears are characterized by their oval form, and 

 are rather shorter than the head. The length of the head and body is two inches, 

 and the span of the wings nine inches. The fur is brownish black at the base, and 

 usually reddish brown on the upper parts and ashy gray below ; although there is 

 considerable individual variation in this respect. 



This bat is chiefly characterized, so far as habits are concerned, by its partiality 

 for the neighborhood of water, and from this peculiarity it is frequently overlooked, 

 even in districts where it is abundant. So close, indeed, does it fly to the surface 

 over which it skims, writes Professor Bell, that it is "difficult to distinguish 

 between the creature itself and its reflection. The flight, quivering and slow, is 

 performed by very slight but rapid strokes of the wings. It may, indeed, be said to 

 vibrate rather than fly over the surface of the water. It could not well fly in any 

 other manner so near the surface without often striking it, and this it seldom, or 

 perhaps never, does, although it often pauses to dip its nose into the water, whether 

 to drink or pick up some food we have been unable to ascertain. The Daubenton's 

 bat is, we suspect, rather an abundant species in the middle parts of England ; at 

 least it is plentiful in some parts of Warwickshire. We have sometimes seen these 

 bats so thick on the Avon, near to Stratford, that at certain spots there could not 

 have been fewer than one to every square yard, and this abundance has extended 

 over a very considerable space. It resorts indiscriminately to buildings or trees 

 during the day, though we think the preference is given to the former." The last 

 observation is in harmony with the opinion of Dr. Dobson already quoted, in which 

 it is stated that the species with the large feet choose buildings for resting places in 

 preference to trees. 



