1. MYCETES. 39 



fur, when it is bent back and examined, as to mako one almost 

 doubt if the black specimens are not another stato or. local variety 

 of the red ones. — Ann. and Mag. JV. II. 1845, xvi. p. 217. 



M. I. Geofiroy states there can be no doubt that M. niger and M. 

 stramineus of Geoffroy are the same species, M. niger being the males, 

 and M. stramineus the females and young. There are in the Jardin 

 des Plantes young males changing into the black state. Stcntor 

 jlavicaudatus, Gooff., is a variety, and S.fuscus, Geoff., a pale speci- 

 men of Mycetes ursinus. (Sco Cat. Mus. Paris, p. 53.) 



Slack observes, "Dr. Graylaj^s great stress upon the toxturo of the 

 hairs as a specific distinction. In M. scnicuhis the hairs of the adult 

 are soft to the touch, while thoso of tho young aro hard and rigid." 

 —Journ. Acad.N. 8. Phil. 1862, p. 51G. 



The species may be divided thus : — 



1. Forehead high, with the hair refloxed, forming a ridge across 



the centre of the crown. 



a. The fur rather rigid in 1, 2, 3. 



b. Fur soft, silky, elongate, 4, 5. 



2. Forehead with tho hair directed forward ; crown smooth, with 



radiating hairs. 



a. Fur short, rather rigid in 0, 7, 8. 



b. Fur rather soft, 9. 



c. Fur very long, silky, 10. 



1. Mycetes ursinus.' i The Araguato. 13. M. 



Brown or blackish, yellow-washed ; hairs rather rigid, brown, 

 with yellowish tips. Malo, female, and junior. 



Mycctcs ursinus, Dcsm. Mamm. ; Pr. Max. Ahbild. t. ; Gray, Ann. 8f 

 Mag. -N. It. 1845, xvi. p. 218. Stontorflavicaudatus, Geoff. Siinia 

 ursina, Ilumb. S. guariba, Humb. Mycetes fuscus, Kuhl ; Spix, 

 Bras. t. 30. 



Var. Yellow ; the tail, head, feet, sides of the head, body, and 

 limbs yellow. Male. P.M. 



M. stramiueus, Spix, Bras. t. 31. M. barbatus, foom., Spix, Bras 

 t. 33. 



Ilab. Brazil. 



2. Mycetes seniculus. The Golden Howler. P.M. 



Reddish chestnut ; middle of the back golden yellow ; hair one- 

 coloured to the base, short, rather rigid, without any underfur ; 

 hair of the head short. Males and females. 



Alouate, Buff. II. N. xv. p. 5 ; Suppl, vii. 1. 15. Simia seniculus, Linn. 

 S. N. i. p. 37 ; Gray, Ann. $ Mag. N. II. 1845, xvi. p. 219. My- 

 cetes seniculus, Kuhl. Royal Monkey, Fcnn. 



JIab. Brazil ; Guiana. In Polivia a paler variety. 



