OCR Text |
Show 1879.] PROF. A. H. GARROD ON GELADA RUEPPELLI. 453 » culated in tbe female. This area extends forwards for three and a quarter inches, broad opposite the mons veneris, which is therefore nude, the anterior border being non-carunculated, and gradually lost in the sparse hair of the abdomen. Osteological comparisons between Gelada and its allies are very attractive, but do not lead to very definite results. Those most important in m y estimation will be here recorded. The following are measurements of the larger bones in the male:- inches. Length of humerus 7*1 ,, radius 7*4 ulna 8*35 femur 7*45 tibia 7-6 „ fibula 7*0 „ scapula , 5*25 (extreme) From anterior margin of praemaxilla to occiput 6*5 (5*8 in $ ) Extreme breadth at posterior parts of zygomata 4*1 (4*0 in 5 ) Extreme breadth of orbit 0*9 (same in $ ) Interorbital interval 0*425 (0*35 in $ ). There are 13 pairs of ribs, of which 5 are false. The sacrum consists of three vertebrae. The clavicles form a single curve ; and the anterior margin of the manubrium sterni is not much thickened. M y opportunities for examining the skulls of adult specimens of Monkeys being but few, it is impossible to generalize to any extent with safety. Cercopithecus differs from Macacus and Cynocephalus in not possessing a fifth lobe to its mandibular third molar. In Gelada this extra lobe is large, as is the anterior talon on the maxillary molars, which are small in Cynocephalus, and much smaller still in the Macaques I have examined. In Gelada the upper incisors are at right angles to the alveolar margins of the premaxillary, which is the case in Macacus; in Cynocephalus and Cercopithecus they converge as they descend. The profile view of the Gelada's skull exhibits the great anterior development of the sharp median portion of the supraorbital ridge and the deep concavity of the nasal contour. In Gelada, Cercopithecus, and Cynocephalus the nasal bones are separate, elongate, and narrow, appearing superficially upon the skull as high as the supraorbital frontal ridge. In Macacus they fuse, and form a short broad triangle whose apex does not reach the frontal bone, the maxillaries meeting above it. In Gelada there is no trace of any groove or foramen for the supraorbital vessels and nerve. This is also the case in Cercopithecus. In Macacus and Cynocephalus, however, the groove is very deep, almost forming a foramen. The malar foramen is also wanting in Gelada. Its presence in allied genera is uncertain. There is a foramen in the fronto-malar suture. |