nonsoNtA. 459 



Vespertilio eephalotes, leaving Hypoderma as a name of C. pcroni ; 

 hut as Hypodenna is preoccupied in Entomology, O. peroni remained 

 in reality without a technically acceptable generic name, until 

 Dohsonia was proposed by Palmer, in 1898. 



Synopsis of the Groups and Species. 



A. I'remolars aud molars simple ; no well-marked 



antero-internal aud posterior basal ledges, no 



surface-ridges A.I). MiNoii group. 



a. Smallest species, forearm about 80 mm. 



(N.W. New Guinea) I . B. minor, p. 460. 



B. A well-marlced antero-internal basal ledge (or 



cusp) at least in p'' and pj, a posterior basal 

 ledge at least in p'', p,, and p4, a median 

 surface-ridge (or cusp) at least in m' and ru^, 

 often also in p* and nij. 



I. Autero-internal corner of uii not differenti- 



ated as a distinct cusp or ledge B. D. moluccensfs 



rt. Much smaller : c-ni" (crowns) 19'8 group 



21-3 mm., forearm 109-116. 

 «'. Rather larger : skull 52 mm., c-nr 



20'5-21'o, maxillaiw teeth on the 



whole heavier, forearm about 112'5- 



116 ; surface-ridge distinct in m', mj, 



and m.,. (Celebes) 2. D. exolda, p. 461. 



b'. Rather smaller : skull 47-48 mm., c-m'^ 



about 198, maxillary teeth on the 



whole weaker, forearm about 109-112 ; 



surface-ridge distinct in m^ and m^, 



rarely (if ever) in m,. (Trobriand ; [p. 463. 



B'Entrecasteaux ; Louisiade Arch.) . , ',',. I), pannietensis, 



b. Much larger, with relatively considerably 



heavier dentition : c-m- 24'o-27'8 mm., 

 forearm 133-5-152-0. 

 c'. Forearm about 133'o-141 mm. (Am- [p. 464. 



boina group : Arn Is.) 4. 7A moluccensis, 



d' . Forearm about 146-1 52'5 mm. (New 



Gidnea ; IMysol ; Waigeou) 5. D. mayna, p. 466. 



II. Antero-internal corner of nij sharply marked 



off as a distinct cusp or ledge. 



c. No well-marked antero-internal basal ledge 



in m' ; longitudinal ridges of cheek- 

 teeth simple CD. peroni groui', 



e. Skull 48-8 o]-7 mm., c-m= 20-22, 



forearm 1085-117. (Timor group) . . 6, Z). joerwM, p. 467. 

 /'. Skull 46-5 mm., c-m' 188, forearm 106. [p. 471. 



(Sumba) 7. D, sumbana, 



(I. Antero-internal corner of m^ sharply 

 marked oft" as a distinct ledge ; general Iv 

 a more or less distinct notch in Icmgi- 

 tudinal ridges of p*, m', p,, and m, behind 



main cusp of ridge D. U. ViuiDis group, 



//'. Foreainn 111-128'5 mm. 



a-. Lachrymal breadth of rostrum ITO- 

 12 8 mm. 



