that of Mycetes. Nevertheless Professor Weldon[1] has found in a female of C. gigot a patch of ossification on the thyroid cartilage of the larynx which may be an indication of something more in the male. There are eleven species.
Nyctipithecus, the Doroucouli Monkeys, is a genus of somewhat Lemurine appearance, caused by their large eyes. But they reminded Bates of an Owl or a Tiger-cat! They have a long, but not prehensile tail. As in the Marmosets, the lower incisors project forwards in a Lemurine fashion. The thumb is very short. A peculiarity of this genus is the twenty-two dorso-lumbar vertebrae. As in Chrysothrix, but not as in Callithrix, the hemispheres of the brain are smooth. There are five species, of which one occurs so far north as Nicaragua; the rest are Brazilian, extending down to the Argentine.
Fig. 266.—Red-faced Ouakari. Brachyurus rubicundus. × 1⁄5.
The Ouakari Monkeys, Brachyurus,[2] are, as the name denotes, short-tailed forms. Two species, B. rubicundus and B. calvus, have bright red faces; B. melanocephalus has a black one. There is a small thumb. The brain is fairly convoluted, and is to be specially compared with that of Cebus and Pithecia. The
