IXTKRKKr.MrOXS OF GJKN-ERA. j; 



have oxisfod which, though essentially similar tc a Pta-opu, i„ tlie 

 Renenil appearance of the skull (palate narrower than in liou.ettn, 

 occiput rather more » subtubular " than in nonsettu. but less so 

 than in Ptcropus, tympanic ring thin) and with the whole series of 

 cheek-teeth unmodified Eousettine or Pteropine in number ("_ •'*) 

 nnd structure, differed in the following important dental characters'- 



rtnnlT'l ''"'r' .r''' '^'1^"J' P'-°^'i^-°^i-^ the lower canines 

 Mtnated close together at the extremity of the mandible, tl>e 

 nner pair of incisors above and below fi> and i, ) had disappeared, 

 the Mngl. pair of lower incisors (i^) was quite small, the sinc^e 

 pair of upper incisors (i^) somewhat modified in shape (crown 

 obliquely triangular or obliquely bilobed, owing to it beini actid 

 ^.pon not by ,,, which was wedged in between the closely app'ox ! 

 mated lower canines and much too small to reach i=, but by the 

 tip ot the lower canines), and, as consequences of these modi- 

 fi.'ations o the front teeth, the premaxilhx. were con iderablv 

 reduced ,n breadth (sublinear) ; externally this bat must have beef, 

 ^cry hke a liovsettvs: tail i>resent (at le.ist about the length of 

 l.e foot), second finger clawed, wings from sides of back aiK 

 n.scrted posteriorly on first or second toe, colour of fur some dark 

 IS 1 iT^Vn" ^^"-^^«r"' ^'^-^ P'-obably as a small lionsett..,. 

 If not smaller still. From this bat have developed in one direction 



mZ:^. ^^"^^'•°-^^^'«^-)' -^ --t^.or//.,,,,/j„,,.,,,.(^MS!n: 



^.iL^t^Tt r^^^'K^ '^'"'''' ^''"■^'"" ^«'-"^^^'> the following 

 further modifications have taken place: the small p> (which i^ 

 sometimes deciduous in Eouseltru., and usually so in Fteropm) ha, 

 entirely disappeared (cheek-teeth I), the wings arise from the spinal 

 lino of the back, which is therefore completely covered bv the 

 naked membranes, and the claw of the second finger has been lost' 

 T. the most primitive species ot the genus (D. vvuor, Xew Guinea) 

 the molar structure is typically Eousettine, but in all other spec cs 

 it^ IS more or less complicated, by the development of posterior 

 basal ledges antero-internal basal ledges, median surfacl ridges 

 or by a tendency of the outer and inner ridges to break up into 

 two or more cusps (for details see pp. 450-452 and fi- 9.5) ^ 



tvne ffltnlT^^^r"^ ^™"' ^^' above-described su^p^sed proto- 

 t pe Harpyionycteris (one species) has been modified as follows- 

 tt.e upper and lower canines and upper ir.cisor are stron^lv 

 proc ivous (upper and lower canines crossing each other at neaHy 

 r ghfc angles), tlie premaxilla, solidly fused anteriorly with each 

 other and laterally with the maxilla^ an outer secondary cusp ha 

 developed m the upper and lower canines, and a small inner^.usn 

 m the lower canines (which therefore are tricuspidate), the number 

 of cheek-teeth is unchanged (^: p' present), but the tendency in 



n^Inf rr'\°^- ^^'^'^-^^^^ (•"«« ^'>*-^-''«'«^ above) toward a develop- 

 me^nt of posterior and anterior basal ledges and of surface cusL 

 and to a splitting of the outer and inne^ ridges into two or more 



