PLASTIC CPTAKACTERS. xlV 



37_ 42 mm.: — BaUonycteris; ? Chironcnv, jVer/alor/losxvit ; Marro- 



qlossiis ; Syconycteris. 

 43- 49 mm.: — Nanonycteris ; Scotonycteris ; Chirona.v; ?Sph(f- 

 rias; Megdloglossus ; Macroglossus ; Syco- 

 nycteris. 

 50- 59 mm. : — Plerotes ; Micropteropns : Nnnonycteris \ Scoto- 

 nycteris ; ? Caninj/cieris ; Myonycteris ; Cyno- 

 pterus; MeyoTops ; Penthetor; Sjihcerias ; Nyctl- 

 mene ; MeJovycteris ; Nesonycteris ; Notopteris. 

 GO- 69 mm.: — Eousettux-^ Epomophorus •, Casinycteris ; Myo- 

 nycteris; Cynnpterus; Penthetor; Nyctimene\ 

 Eonyctcris ; Melonycteris ; Notopteris. 

 70- 79 mm. : — liotcscttus ; Dobsonia; EpomopJiorns:, C'ynojiteriis ; 

 Dyacopterus ; llioopterus ; Nyctimene ; Eonyc- 

 teris. 

 80- 89 mm. : — Eousettus; Pteropus; Dobsonia; TImyyionycteris; 

 Epomops; Epiomopilwriis ; Cynoptervs; P/eno- 

 cJiirus; Nyctimene; ? Eonycteris. 

 90- 99 mill. : — Pouseftus ; Boneia ; Pteropus ; Sfyloetemmn ; 

 Epomops ; Epomopliorus ; Cynopierus. 

 100-109 mm.: — Pteropus; Dobsonia; Epomops. 

 110-119 mm. : — Eidolon; Pteropus; Dobsonia; ffypsiynatJius. 



[Archcvopteropus would belong here.] 

 120-129 mm. : — Eidolon; Pteropus; Dobsonia; Hypsiynathns. 

 130-139 mm. :—£'?c?o?on; Pteropus; Acerodon; Pteralope.r; Dob- 

 sonia ; Hypsignathus. 

 140-149 mm. : — Pteropus; Acerodon; Pteralope.r; Dobsonia. 

 150-159 mm. : — Pterojms ; Acerodon; Dobsonia. 

 160-205 mm.: — Pterojnts; Acerodon. 

 206-220 mm. -.—Pteropus. 



20. Secondary sexual characters. 



In all or nearly all genera (in so far as both sexes are known) 

 the canines average at least a little heavier and the zygomatic 

 breadth of the skull at least a little greater in males than in females. 

 In several Pteropodino' (some species of Pteropus; Pteralope.r; 

 Penthetor) and the majority of Macroylossince (Macroglossus, Syco- 

 nycteris, Melonycteris, Nesonycteris, Notopteris) this seems to be 

 tlie only tangible secondary sexual differentiation, and even this 

 difFerenco is in some cases so small as to be only appreciable in 

 largo series of individuals. As a rule, however, the differentiation 

 of the soxos is somewhat more conspicuous, the secondary sexual 

 characters being referable to the following four categories : — 



(1) Males of a few genera average noticeably larger than females 

 {Epomops, llypsignathus, and Epomophorus ; Eonycteris). 



(2) The general colour of the fur is in a few species conspicuously 

 lighter in females than in males (some species of Eidolon and 

 Nyctimene) ; or males average poraeNvhat richer in general colour 

 than fomnles (Dobsonia riridis). 



