Xii.IV PLASTIC CnARACX'EliS. 



angular process, and the lower dowu the position of the condyle, 

 Tliere is within the suborder every gradation from the unusually 

 heavy mandible with nearly vertical coronoid process, deep and 

 broadly rounded angular jjrocess, and the cond\le situated high 

 above the alveolar line, of Pteratopex (fig. 21, p. 433j, Acerodon 

 (fig. 20, p. 413), the heavy-toothed species of Pteropus (fig. 14, 

 p. 281) ; fig. 15, p. 302), Dohsonia (fig. 24, p. 449), and most genera 

 of the Cyuopterine section (fig. 48, p. 588 ; fig. 61, p. 684), through 

 the intermediate conditions as exhibited in the Epouiophorinc 

 section (fig. 30, p. 488 ; fig. 40, p. 560), to the mandible as shaped 

 in the narrowest-toothed Macroi/Iossina; (fig. 70, p. 748), with 

 its short, thin, and posteriorly directed coronoid process, weak 

 angular process, and condyle situated considerably below the level 

 of the alveolar line. 



The symphysis of the mandible is in the Pteropodince usually 

 obliquely ascending, more rarely (ex. Dohsonia, Nyctimcne) sub- 

 vertical ; in the Macroglossince as a rule more nearly horizontal. 

 In some genera of Macro(jlossince {Eonijdcris, Mei/alor/Jossus, Macro- 

 (jlossus, Mdonycteris, Nesomjcteris) there is a more or less clearly 

 pronounced tendency to a development of a longitudinal keel 

 along the antero-inferior surface of the symphysis. 



9. Incisors. 



Incisor formida'. — i^ is lost in all Chiroptcra ; ij is present in 

 many Microchiroptera, but lost in all Mcgachiroptora (the incisors 

 of Arclia'opteropus are unknown) ; no Fruit-bat, therefore, has more 

 than % — 5 incisors, but some have less. The following five incisor 

 formuliB occur : — 



i- iMM 2 2 



.-. = , the normal formula, found in all genera except 



'^ 'i 'i '-^ ^ , ^ 



those enumerated below. 



j2 i^ 1 1 . 



= , in one genus, Boneia (allied to lioitsetfus). 



\h\h ^' ^ 



42 \\ p V- 9 2 . ■ 



= , in one genus of the Ptcrojms subsection, viz. 



Sh/locfe7iium ; in four genera of the Cynopterus section, 



ptcnochirus, Megcurops, Balionyctcris, and Penthetor; 



and in two Macroglossine genera, I\esonycicris and 



JS'otoptcris (in the latter i^ is deciduous). 



;2 i^ 1 1 



= , in Dohsonia and Ilarpyionyctens^ both aberrant 



i., ij 1 ■'^ 



genera of the Pousethis section (on the homologies of 



the missing incisors in these two genera, see footnotes 



p. 452 and p. 801). 



- i'i' - 1 1 



Z = , in Kiictimcnc onlv, a i)eculiar]v modified genus of 



the Cynopterus section. 



