1876.] DR. G. E. DOBSON ON MYSTACINA TTJBERCTJLATA. 487 



culata, none are more remarkable than the presence of a third pha- 

 lanx in the middle finger, a character in which it differs from all 

 other species of the family (Emballonuridae) to which it belong*!, and 

 agrees with those of a distinct though allied family, the Phyllosto- 

 midse, which are limited to America. 



The middle finger consists of a metacarpal bone and three pha- 

 langes. The first phalanx, instead of being folded (in repose) upon 

 the dorsal surface of the metacarpal bone (as in the other species of 

 Eniballonuridee) is flexed downwards, inwards, and forwards upon 

 the inferior surface of the metacarpal, carrying with it the corre- 

 sponding phalanx of the third finger, which lies folded downwards 

 and forwards, between it and the metacarpal bone ; the second pha- 

 lanx is folded backwards on the first ; and the third phalanx is folded 

 forwards on the second. Being thus reduced by this peculiar fold- 

 ing process into the smallest possible space, the wing is then tucked 

 in beneath the thickened portion of the wing-membrane margining 

 the forearm and side of the body, which sheaths and completely 

 conceals the whole wing. The posterior half of the interfemoral 

 membrane, from the point where the tail perforates it, is rolled up- 

 wards and forwards beneath the leathery anterior half. With the 

 wing- and interfemoral membranes thus encased, this species is the 

 most quadrupedal of Bats ; and the peculiar development of the ex- 

 tremities, which I shall now describe, indicates special powers of pro- 

 gression. 



Fig. a. Fig. b. 





Thumb and sole of foot of Mystacina tuberculata. 



The thumb is long, and armed with a large and very acute claw, 

 which has a small talon projecting from its concave surface near the 

 base (fig. a) ; the feet have similarly long and very acute claws ; and 

 at the base of each a similar talon is placed (fig. b). This peculiar 

 basal talon has not been before observed ; and I believe it does not 

 occur in any other species of known Bats. A similar talon is found 

 at the base of the claws in the short-tailed Chameleon, Rhampholeon 

 spectrum, which is thus described by Dr. Giinther in his description 

 of that species : — " The tail is so short that it can serve as a prehen- 



