HOWLING MONKEYS. 185 



THE BLACK HOWLER (Mycetes caraya). 







We select as our first example of that group of howlers in which the hair of 

 the forehead is directed forwards so as to overhang the eyes, and the crown of the 

 head is smooth, with radiating hairs, the black howler, either a young male or 

 female of which is alluded to in the passage cited above. 



It is a native of Brazil. The adult males have their fur mainly of a uniform 

 black colour, interspersed with red hairs on the flanks and loins. The females 

 and young males are of a dingy white, and were described as belonging to a distinct 

 species, under the name of M. stramineus. At one time there were young males of 

 the black howler in the Jardin des Plantes, at Paris, which actually changed from 

 the white into the black state. Mr. Bates's example was obtained on the Madeira 

 River, the largest southern tributary of the Amazon. 



The yellow-handed howler (M. belzebul) is another Brazilian representative of 

 this group, which has been known since the time of Linnaeus. It appears to vary 

 considerably in colour, so that one variety was described as a distinct species (M. 

 l1<i I'tniciniis). According to the late Dr. Gray, the general colour of the fur may be 

 either uniform black or reddish, with some brown hairs on the shoulders ; but the 

 hands and feet, as well as a line running down the middle of the upper surface of 

 the tail, the tip of the same, together with a spot in front of each ear, and another 

 on the knee, are invariably reddish-yellow. Mr. Bates states that the variety 

 which is reddish coloured all over is the prevalent type of howler in Para, on the 

 southern side of the delta of the Amazon ; while in the island of Marajo, or Macajo, 

 in the middle of the delta, this form is replaced by the darker one with yellowish 

 hands and feet. 



The red-and-yellow howler (M. auratus) is a third species from Brazil belong- 

 ing to this group, in which the general colour is dark chestnut-brown, with the 

 back and sides golden yellow, and the beard somewhat darker. Dr. Gray also 

 applied distinct names to two other Brazilian howlers. 



OTHER SPECIES. 



vera Cruz As the black howler is the most southerly representative of the 



Howler. genus, so M. villosus, the Yera Cruz howler (of which the head is 

 figured on p. 183) is its most northerly example. This species differs from the 

 black howler by its long soft hairs, which near their bases show a rufescent tinge, 

 in the hair of the face being inclined forwards instead of reversed, and also in the 

 colour of the female and young being black, like that of the male. 



The red or golden howler (M. seniculus) is perhaps the best- 

 known representative of the group in which the hair is bent back 

 so as to form a ridge across the centre of the crown of the head. The general 

 colour is a reddish-chestnut, but golden-yellow in the middle of the back. It 

 appears that in young individuals the hairs are short and stiff, without any under- 

 fur, and uniformly coloured throughout their length. In older individuals, how- 

 ever, they become long, soft, and silky, and are brown at the roots, and golden or 



