The term Mona means tailed Apes or Monkeys, and it has been especially given to one from Senegal, which has some resemblance to the Diana, and it is mentioned here with a view of illustrating its mental peculiarities. They are more beautiful in colour and more elegant in form than the Diana, and they are sometimes more gentle, sagacious, and sharp than any other kind. F. Cuvier describes one which was a great favourite in the collection at Paris. Upon his arrival he was extremely young, and his gentleness and total want of malice and petulance gained him the free range of the apartment. Age did not alter the excellence of his disposition; and as he increased in age and strength, his address and agility became unparalleled. Yet all his motions were gentle, and his actions circumspect; he was persevering in his wants and wishes, but never violent in the attempt to enforce them. When after much solicitation his requests were refused, he would go off in a gambol, and find entertainment in some new object. He had no idea of property, but took every thing that pleased him, even such articles as had previously caused him punishment, and he committed his thefts with dexterity and silence. He would open locks wherein the key had been left, untie knots, open the links of a chain, and search pockets with so much address that you did not feel his hand there, although conscious of the fact that he was thieving. The examination of pockets was his favourite occupation, doubtless from expecting to find food. He was not very affectionate, but when tranquil, and not engaged, he received caresses with pleasure. When tempted to play he signified his assent by many graceful motions; he would throw himself into all sorts of graceful attitudes, bite gently, press himself against you, and give out a gentle cry. He never made grimaces, but, on the contrary, his countenance was always calm, and frequently serious. He looked a perfect angel of a Monkey in his beautiful fur; his hair was of a brilliant golden green, the back and sides were rich brown, variegated with black, the outer part of the limbs and tail were slate-coloured grey, while the neck, chest, and underneath were pure shining white. He had ears and hands of a flesh-colour, and there was a black band stretched across the forehead, surmounted by a crescent-shaped stripe of grey. [Illustration: WHITE-NOSED MONKEY.] Probably its French education may have had something to do with its politeness and gentleness, for one of these pretty creatures which was kept in the Zoological Gardens was one of the most ill-conditioned savage beasts ever seen--quite a diabolical Monkey. This Monkey does not appear to have the air sac in the neck which is common to the Guenons, as well as to the other Monkeys already noticed. THE WHITE-NOSED MONKEY.[42]