INTRODUCTION. XI 



in Chalinolobus (Plate XIV. fig. 5 a) and Miniopterus, where, al- 

 though the ear-conch is small, the hullce ossece are remarkably large. 

 The tympanic is thin-waUed and very loosely connected with the 

 surrounding bones, and does not develop an external canal ; the 

 spiral turns of the cochleae are generally distinctly visible externally 

 through the very thin walls of the capsule, and in some species 

 number as many as four. In the Bhinolophidm the auditory buUce 

 ossece attain their greatest size (especially in the genus Rhinolophus, 

 where they nearly meet in the middle line, the intervening basi- 

 occipital bone being reduced to a narrow isthmus) ; and it is note- 

 worthy that in these Bats the tragus is not developed*. 



Paroccipital processes are present in most of the genera; they 

 reach their greatest development in Megachiroptera, where they are 

 rather long and narrow ; in Microchiroptera they are comparatively 

 much smaller, especially in the family Vespertilionidm. 



The shoulder-girdle varies very slightly in the different families, 

 having the same office to fill in all. The clavicle is always very 

 strong, long, and curved ; the scapula large, oval-triangular in ou<^ 

 line ; the postscapular fossa greatly exceeds the anterior fossa, and is 

 deeply concave for the origin of the large muscles arising therefrom ; 

 the spine of the scapula is well developed, with a large acromion ; 

 the coracoid is long and curved. 



The humerus is long, but compared with the radius is scarcely 

 two thirds its length ; the form of its upper extremity varies very 

 slightly ; the external and internal tuberosities are prominent, the 

 internal being the larger ; the pectoral ridge is enormously developed 

 for the insertion of the great pectoral muscle, and the inner side of 

 its base is marked by the groove for the deltoid tendon ; the shaft 

 of the humerus is smooth and cylindrical ; the distal extremity has, 

 in all species, a large entocondyloid tuberosity, which, in some 

 species (especially in the species of Rhinolophiclm) is very large, in 

 the genus Tricenops developing a long styloid process f ; the articular 

 surface is marked by a deep sigmoid notch ; there is no anconeal 

 fossa nor supracondylar foramen. The ulna is rudimentary ; its 

 proximal extremity, which articulates with but a small part of the 

 humerus posteriorly and externally, is anchylosed with the- radius ; 

 immediately beyond the joint it is reduced to a very slender splint- 

 like bone more or less curved backwards and separated from the 



'* See remarks on the tragus, infrii, p. xix. 



t See plate vi. figs. 4, 4 a, Journ. Asiat. Soc. Beng. pt. ii. (1872), referred to 

 above, in footnote, p. Tii. 



