THE BRITISH MAMMALS : ORDERS, FAMILIES, ETC. 17 



extends very slightly beyond its inner margin ; there are two 

 phalanges in the middle finger, the first being extended in repose in 

 a line with the metacarpal, and the middle pair of upper incisors 

 are small and set wide apart from each other. 



The Rhinolophidae have a complex leaf around the nasal 

 apertures, and no tragus, or earlet, in the ears. The premaxillaries 

 are rudimentary and hang from the nasal cartilages, carrying a pair 

 of rudimentary incisors. The first upper premolar is minute, and 

 the lower incisors are tricuspid. The only bone in the index finger 

 is the metacarpal. The skull is large, the nasal bones being 

 expanded to carry the nose leaf; the tail is long and extends to the 

 end of the interfernoral membrane. The only British genus is 

 Rhinoloplms (Plate I., i, 2). 



The Vespertilionidas have a tragus and no nose-leaf. The pre- 

 maxillse are small, lateral, and wide apart in front. There are two 

 phalanges in the index finger as well as the metacarpal. The skull 

 is not comparatively large, the nasal bones not being expanded. 

 The tail ends at the edge of the interfernoral membrane or very 

 little beyond it. The British genera are Plecotus, Synolus, Vespertilio, 

 and Vcsperugo (Plates I., II., III., 3 to 15). 



In the Insectivora the feet are more or less plantigrade, and 

 generally have five digits, all with claws. The skull is low, the 

 cranial cavity small, the facial region long, and the snout projects 

 beyond the lower jaw. There are more than two incisors in the 

 mandible, the canines are generally weak, and the molars are coated 

 with enamel and have tuberculated crowns and well-developed 

 roots. Of the ten families three, Erinaceidae, Talpidae, and Soricidae, 

 are represented in Britain. 



The Erinaceidas have plantigrade feet, with the claws not modi- 

 fied for digging. The radius and ulna are well developed, but the 

 fibula is consolidated with the tibia. The clavicles are long and 

 slender. The skull is without postorbitals, but has a ridge and 

 process in front of the orbit. The nasals are separate ; the tympanic 

 is annular, and is not inflated into a bulla. The upper molars are 

 broad with many cusps, the crowns being zigzagged; the first and 

 second upper molars have a central fifth cusp. There is but one 

 genus on the British list, Erinaceus (Plate IV., 16). 



The Talpidae have the fore legs more or less modified for digging 

 purposes and placed well forwards. The clavicles and humerus are 

 short. The radius and ulna are well developed. The tibia and 

 fibula are united. The pubic bones are widely separated. The 

 skull is long, with slender zygomatic arches; there are no post- 

 orbitals to the frontals ; the tympanic forms a bulla. The upper 

 molars are broad with many cusps, the crown being zigzagged; 

 there is no fifth central cusp to the upper molars ; the front incisors 

 are not directed forwards. The only British genus is Talpa (Plate 

 IV., 17). 



The Soricidae have plantigrade feet with simple claws. The 

 radius and ulna are separate, the tibia and fibula united. The skull 

 is long and narrow; it has no postorbital process to the frontals ; 

 the tympanic is annular ; there are no zygomatic arches. The upper 

 molars are many-cusped and broad, the crowns being zigzagged ; 



