Proceedings of the Scientific Meetings of the Zoological Society of London 1867

Page 1071

992 DR. J. E. GRAY ON A NEW ATELES. [ Dec. 12, In the Museum there is a specimen of an Emu's egg containing the chick-bones at about the same stage of development. On comparing these two specimens, the principal difference con­sists in the dense brittle character and white colour of the E m u bones as compared with those of the Moa chick, and in the enor­mous disproportion in the massiveness and form of the bones of the extremities in the latter case, with the very slight difference in the size of the cranium and total relative height of the embryos. The specific gravities of these bones are respectively- Moa chick 1*538 E m u chick 1*577 Bone of old Moa 1*700 to 1*979 The comparative length of the principal bones of these chick-ske­letons are as follows : - ,.„ .. , w ,. , Moa chick. Lmu chick. inches. inches. Cranium 2*1 2-0 Pelvic bones 2-6 1*6 Femur 1*7 1*2 (Diameter of shaft *35 in.) (Diameter of shaft *28 in.) Tibia 3*0 21 (Diameter of shaft *35 in.) (Diameter of shaft *16 in.) Fibula 2*0 15 Tarso-metatarsus 1*9 1*8 Probable total length of Moa chick 14*5 inches. Probable total length of E m u chick 13*0 inches. Weight of bones of extremities and pelvis- In the M o a chick 167*0 grains. In the E m u chick 40*5 grains. Or in the proportion of 4 to 1. 7. Description of Ateles bartlettii, a N e w Spider Monkey from the River Amazons. By Dr. J. E. G R A Y , F.R.S., V.P.Z.S. & c (Plate XLVII.) One of the most important zoological results of Mr. Edward Bart­lett's exploring excursion up the River Amazons has been the disco­very of a new Spider Monkey *, which differs from all the species of this usually lugubrious genus in the brightness and beautiful dis­position of its colours. Mr. Wolf has made a beautiful drawing of this specimen, which is now in the British Museum collection. ATELES BARTLETTII, sp. nov. (Pl. XLVII.) Fur abundant, long, and soft. Black ; the cheeks white ; a band across the forehead over the orbits bright reddish yellow; the chest, * See Mr. Bartlett's notice of the discovery of this species, P. Z. S. 1867, p. 2.