i86 
APES AND MONKEYS. 
chestnut - coloured at their tips; while at the same time a thick under - fur is 
developed. It was old individuals with this long silky kind of hair that Dr. Gray 
described as a distinct species, under the name of the silky howler (M. laniger). 
This howler appears to be mainly a northern form, occurring in Colombia 
on the west, and in Guiana on the east side of South America; while, according to 
Mr. Bates, who describes its fur as being of a shining yellowish-red colour, it is the 
sole representative of the howlers in the Upper Amazon valley. It also occurs in 
Ecuador; and, according to Dr. Gray, is represented by a pale variety in Bolivia. 
The red howler is one of the two species of this genus that have been exhibited 
in the Gardens of the London Zoological Society. It is, however, difficult to keep 
alive for any length of time, and of two specimens received from the Dekka Biver, 
near Cartagena, on August 28th, 1863, the one died on September 25th, and the other 
on October 7th of the same year. Writing of these howlers, which he states are 
known to the natives as ouarines, and on the Demerara in Guiana are commonly 
known as red monkeys, the traveller Charles Waterton states “ that nothing can 
sound more dreadful than the nocturnal howlings of this red monkey. Whilst 
lying in your hammock amid these gloomy and immeasurable wilds, you hear him 
howling at intervals from eleven o’clock at night till daybreak. You would 
suppose that half the wild beasts of the forest were collecting for the work of 
carnage. Now it is the tremendous roar of the jaguar, as he springs upon his 
prey; now it changes to his terrible and deep-toned growlings, as he is pressed on 
all sides by superior force; and now you hear his last dying groan beneath a 
mortal wound. Some naturalists have supposed that these awful sounds, which 
you would fancy are those of enraged and dying wild beasts, proceed from a 
number of red monkeys howling in concert. One of them alone is capable of pro¬ 
ducing all these sounds; and the anatomists, on an inspection of his trachea 
(windpipe), will be fully satisfied that this is the case. When you look at him, as 
he is sitting on the branch of a tree, you will see a lump in his throat the size of a 
hen’s egg. In dark and cloudy weather, and just before a shower of rain, this 
monkey will often howl in the day-time; and if you advance cautiously, and get 
under the high and tufted trees where he is sitting, you may have a capital oppor¬ 
tunity of witnessing his wonderful powers of producing these dreadful and dis¬ 
cordant sounds. Thus one single solitary monkey, in lieu of having others to sit 
down and listen to him, according to the report of travellers, has not even one 
attendant. Once I was fortunate enough to smuggle myself under the very tree, 
on the higher branches of which was perched a full-grown red monkey. I saw his 
huge mouth open; I saw the protuberance on his inflated throat; and I listened 
with extreme astonishment to sounds which might have had their origin in the 
infernal regions.” 
The brown howler (M. ursinus) is a Brazilian species, apparently 
Brown Howler. v 1X1 J 
found only or chiefly south of the Amazon. Its usual colour is a 
blackish-brown, more or less washed with yellow; and some varieties are almost 
entirely yellow, this being most marked on the limbs and tail. The howler 
described as M. fuscus, of which specimens have been exhibited in the London 
Zoological Society’s Gardens, is regarded by Dr. Gray merely as a variety of this 
species. It has been observed that the specimens of this monkey from the more 
