Glass 6. Mammalia. Order 4. Chiroptera. 601 



forearm are also elongate, although to a relatively small extent. The 

 hind legs are turned outwards in a peculiar way ; they are thin and 

 feeble : a long, thin bone or cartilage, the spur, arises from the 

 ankle ; it lies on the edge of the membrane extending between the 

 hind limbs. The patagium can be folded up like an umbrella, and 

 laid along the body. The clavicles are long and powerful, the pre- 

 sternum provided with a long keel. The mammillge, one or two pairs, 

 are thoracic* The Bats are nocturnal or crepuscular. Their best 

 mode of locomotion is flight, but they can manage to crawl on their 

 hind limbs and thumbs. They rest suspended by the hind feet. 



1. Large Bats (MegacMroptera : genus Pteropus, fhe Fruit-Bats or 

 Plying Poxes, etc.). Olaws on the first and second digits; head long; 

 molars with two longitudinal ridges ; pinna simple : chiefly frugivorous. Large 

 forms inhabiting the warmer parts of the Old World and Australia. 



2. Small Bats [Microchiroptera). There is no claw on the second finger ; 

 head short; molars with several tubercles (like those of the Insectivora) ; opening 

 into the external auditory meatus more or less completely covered by a 

 membranous flap of the pinna, the anUtragus. They feed principally on Insects, 

 which they catch as they fly, discovering them by the tactile sense located in the 

 skin, especially of the patagium, of the pinna, which is sometimes very large, and 

 of peculiar outgrowths (nasal processes), which are frequently present on the 

 head. Some South American forms (T a m p i r e , Besmodus) suck the blood of 

 other living Mammals. The group is very rich in species, distributed over the 

 whole world, especially abundant in the tropics ; mostly small animals. A fairly 

 large number of diverse forms occurs in England ; among them may be noted : 

 several species of the genus Vesperugo, of which the Pipistrelle (V. pipis- 

 trellus) is the common English one. This genus is characterised by the shoi-t 

 antitragus, and by the possession of *f^ cheek teeth : of the genus Vespertilio, 

 Daubenton's Bat {V. daubentoni), is a well-known British species, with a 

 large antitragus and f cheek teeth : of the Horse-shoe Bats (Rhinoloplius), 

 the greater (iJ. ferrum-egwinutn), and the lesser (iJ. hipposiderus), both occui- 

 in England although they are not vei-y common ; they are distinguished by the 

 complicated nose-piece. All the British species hibernate, passing the winter 

 suspended in hollow trees and elsewhere. 



Order 5. Ungulata. 



The limbs are elongate and specially adapted for walking or 

 running, the trunk is raised well above the ground. The metacarpus 

 and metatarsus are usually of considerable length ; the digits are more 

 or less completely enclosed in a common skia (with the exclusion, how- 

 ever, of the last) ; the animal usually steps upon the last phalanx only, 

 chiefly upon the surrounding hoof (p. 470) ; the rest of the foot does 

 not touch the ground, but assists in lengthening the limb. The first 

 digit and the corresponding meta-carpal or tarsal is absent from all 

 four limbs of all existing Ungulata. Clavicles are also wanting. 



* Many indigenous Bats are very remarkable in that whilst copulation occurs in. 

 the autixmn, fertilisation of the ovum does not take place till the following spring ; 

 the spermatozoa are stored in the uterus of the female during hibernation. 



