246 ALLEN’S NATURALIST’S LIBRARY. 
feet above the sea, on the Orizaba volcano, and in the forests of 
Oaxaca, to 4,000 feet. Mr. Salvin, on the volcano of Atitlan, in 
Guatemala, at a height of between 5,000 and 6,000 feet, met 
several troops of this species on the tops of the higher trees 
of the forest. ‘These parties of Monkeys were usually about 
twenty in number and of all ages. On approaching them they 
did not evince any alarm, but kept uttering a constant queru- 
lous sort of bark, and moved from time to time so as to get a 
better view of the intruder. A few days afterwards, during 
an excursion to the same volcano, when the summit, 11,800 
feet above the sea, was reached, numerous troops of A/e/es were 
seen in the forest, from an elevation of 7,000 feet to as low as 
2,500 feet on the outskirts of the coffee plantations of San 
Agustin. 
Now that we have passed in review the whole of the Anthro- 
poid species inhabiting the New World, a short account of the 
regions to which they are confined will be of some interest. 
The most northern limit of Monkeys is, as mentioned above, 
the State of San-Louis Potosi, about the latitude of 23° North. 
Their most southern limit attains to nearly 25° of South lati- 
tude. They are now confined to the Mexican and Brazilian 
sub-regions of what has been defined as the Neotropical 
Region, by Dr. A. R. Wallace, in his great work, ‘The Geo- 
graphical Distribution of Animals.” The Mexican sub-region 
belongs to the Neotropical Region, one of those six great 
areas into which the globe has been divided off by Dr. Sclater 
on the basis of the geographical distribution of the animals 
that now inhabit it—the final product of the slowly-changing 
features of the earth’s surface, and of the form, structure, and 
habits of its animal and vegetable life. 
The Mexican sub-region forms the northern part of the Re- 
