202 NATURAL SCIENCE. March. 



fact that species also occur in Southern India and Malaysia has 

 caused some zoologists to view with favour the idea of a former land 

 junction between these distant areas. But when we consider the 

 geological distribution of the group, as evidenced by the fossil remains 

 already brought to light, we see that it formerly extended over the 

 land area of Africa and Southern Europe and Asia, and are more 

 inclined to believe that conditions of climate or other causes have 

 determined the present distribution at either end of the earlier exten- 

 sion. Dr. Forbes makes a feature of his geological evidence, and treats 

 of the majority of the remains described by various authors from the 

 rocks beneath us. So far as we know at present, the Lemuroidea 

 appeared in Lower Eocene times, and obtained a considerable 

 development in the Middle Eocene. Zittel has called attention to 

 the fact that in the Upper Eocene of Europe lemuroid genera formed 

 a very characteristic element of the fauna, and the evidence, though 

 less abundant, is perfectly sufficient to permit a similar though not so 

 strong statement as regards North America. By far the most extra- 

 ordinary of all these fossil lemuroids is Megaladapis from Madagascar, 

 an account of which was given in Natural Science (April, 1894, 



P- 243)- 



Following on the Lemuroidea come the Anthropoidea (or true 

 monkeys), containing the Harpalidae and the Cebidae of the New 

 World and the Cercopithecidae and Simiidae of the Old World, both 

 of which two groups are exclusively confined to their own areas. 

 Moreover, no fossil representative of the two former has ever been 

 found in the Old World, nor have any remains of either of the latter 

 families ever been found in the New World, a fact, as Dr. Forbes 

 remarks, which doubtless indicates a separation of great antiquity 

 between the two groups. The chief genera of the Harpalidae and 

 Cebidae are those containing the Marmosets, Capuchins, Woolly 

 Monkeys, Spider Monkeys, Howlers, Sakis, and Squirrel Monkeys ; 

 and their chief habitat is the extensive equatorial forests of the 

 Amazons, the Orinoco, and their tributaries. It is interesting to note 

 that Mr. Salvin has recorded troops of the Mexican Spider monkey at 

 an elevation of 7,000 feet on the volcano of Atitlan ; but as a rule the 

 basal line of a mountainous tract seems to be preferred by these animals. 

 All these New World monkeys are characterised by a flat nose, the 

 opening of the nostrils directed outwards, and the nostrils widely 

 separated by a broad cartilaginous septum ; on this account they are 

 designated Platyrrhini. All the Old World monkeys, on the other 

 hand, have the nose narrow, the nostrils close together and directed 

 downwards, as in man, and separated by a thin septum, or partition, 

 of cartilage ; and from this peculiarity they have received the name of 

 Catarrhini. 



These Catarrhini include the Baboons, and the Guenons of 

 Africa, the Black Apes of Celebes, and the Asiatic Macaques, the 

 curious Nosed-monkeys of Borneo, the Langurs of India and Malaysia, 

 the Guerezas of Africa, and the Man-like Apes. Among the best 

 known forms of the Old World apes are the Chimpanzee, the Gorilla, 

 and the Orang-Utan. The remaining family of the Primates, the 

 Homo sapiens of Linnaeus, is somewhat better known than the rest, and 

 Dr. Forbes dismisses it in some six pages. 



Each genus and species of monkeys dealt with by Dr. Forbes is 

 described in brief but comprehensive terms, and notes are given on 

 its geographical distribution (as recorded), its general habits and 

 characteristics, while a synopsis of the literature connected with it is 

 quoted. When possible, a brief extract from the personal observa- 



