1901.] SKULLS OP LEMURS AND MONKEYS. 149 



encircling completely the fossa and protruding on the face above 

 and below the former. The whole of the fossa is likewise encircled 

 by the lacrymal in a specimen of " M. sinicus " (Br. M. No. 1102 5), 

 but here both maxilla and lacrymal participate in the formation 

 of the crista anterior. 



In the remnant of the skulls of Macacus (63) (PI. XII. fig. 10) 

 the conditions are those described by Gregenbaur (" Inuus "). 

 The same is the case in the few specimens of Inuus ecaudatus at 

 my disposal. 



GercopitTiecus. 



Ninty-five specimens examined. — Here too, as in Macacus, 

 we meet with the two extremes. In 12 skulls — G. cephus (4), 

 0. nictitans, O. melanogenys, C. sp. (Br. M. No. 67.4.12.15), 

 0. erxJebeni, C. sabceus, G. cynosurus, C. mo7ia, G. schmidti, — 

 young and old, the crista anterior is entirely supported by the 

 maxilla, which generally descends into the fossa. In seven skulls 

 the opposite takes place, the fossa being entirely encircled by the 

 lacrymal ; and as the crista anterior is generally flattened, the fossa 

 cannot be said to be inside the orbit — " G. sabceus " (Br. M. 

 No. 20 h), G. cephus (No. 783 e), G. samango (Br. M. No. 14 a\ 

 G. campbelli (Br. M. No. 1078 a), G. albogularis (Br. M. No. 0.2.1.4, 

 No. 92.10.18.8, and No. 92.10.18.9) (PI. XI. fig. 5). In five 

 skulls— viz. : C. schmidti (Br. M. No. 98.10.10.1), " C cephus" 

 (Br.M. No. 783 a), G. albogidaris (Br. M. No. 17 c. No. 92.10.18.7, 

 and No. 17 a) — the crista anterior is almost exclusively supported 

 by the lacrymal. It will be observed that the extreme development 

 of the lacrymal chiefly occurs in the " Melanochiri " group of the 

 genus. 



Gercocebus, 



Five skulls. — In the few specimens of which I have examined the 

 condition of the lacrymal — two of G. cethiops, one of G. albigena, 

 two of G. fidiginosus — the fossa is completely or almost completely 

 encircled in front by the lacrymal. 



Miopithecus. 



Only four skulls have been examined, a young specimen with 

 the deciduous teeth in place, and three adult, one of which has the 

 teeth much worn. In all of them the crista anterior is entirely 

 supported by the maxillary, which encroaches also on the fossa, 

 behind (PI. XII. fig. 9). 



Nesopithecus. 



Por the sake of comparison with both Lemurs and Monkeys, 

 I have reserved for the end the Malagasy subfossil Nesopithecus. 

 As shown by the figures (PI. XI.), the two species, N. australis and 

 N. roberti, present dilferenees in their lacrymal region, dependent 

 on the facial cranium being somewhat more produced in the 

 former than in the latter, in which the profile is steeper. 



