CHARACTERS.--Top of the head with a peaked longitudinal crest; hair of crown not radiating, but elongated and directed backward; whiskers long and outwardly directed, partly covering the ears; back, sides, fore-arm, hands and fore part of the feet blackish-brown, the middle of the back washed with yellowish; the chin, chest, and under surface of the body pale yellow; inside of the fore-arm and thighs brown; face livid, but the eyelids, lips, and a ring round the eyes, white, flushed with flesh-colour; length of body, 18½ inches; tail, 21½ inches. Supra-orbital ridges of the skull not prominent, the occipital region vertical; facial region sloping downward. The Babu Ram Bramha Lányal, writing in July, 1893, from the Zoological Gardens, Calcutta, to Dr. Sclater, says: "I am not aware whether closely allied species of _Semnopitheci_ have ever inter-bred anywhere. They are rather exclusive in their ideas in respect to matrimonial relationship. Anyhow, such an event has just happened in this Garden. The Phayre's Langur, or as it is often called, Phayre's Leaf Monkey (_Semnopithecus phayrii_, Blyth) has given birth to a young one--a lovely little babe, of a delicate light orange colour. As there has been no other male in the same cage except the _S. cristatus_, there is no doubt of the young one being a hybrid between these two species. These Monkeys have been living together since 1880, and although they agreed very well, they were never observed to be over friendly. Even now the male does not appear to take any interest in the offspring." DISTRIBUTION.--Confined, as far as is known, to Aracan. {133}XXIII. RUTLEDGE'S LANGUR. SEMNOPITHECUS RUTLEDGII. _S. rutledgii_, Anderson, Zool. Res. Exped. Yun-nan, p. 38 (1878). CHARACTERS.--Head with a very well-defined erect median compressed crest; frontal hairs not projecting over the face. General colour black, the hairs tipped with lustrous grey on the head, crest, trunk, and limbs. Hands and feet black. Under surface paler and the hairs more tipped with grey; tail black above, yellow below, tipped with grey; whiskers long, backwardly and upwardly divided, and broadly tipped with yellowish-grey; beard greyish; face bluish-black. Length, 17 inches; tail, 24½ inches. (_Anderson._) DISTRIBUTION AND HABITS.--Unknown. XXIV. THE WHITE-FRONTED LANGUR. SEMNOPITHECUS FRONTATUS. _Semnopithecus frontatus_, Müll., Tijds., Nat. Ges., v., p. 136, pls. i. and ii. (1838); Martin, Mammif. An., p. 475 (1841); Gray, Cat. Monkeys Brit. Mus., p. 16 (1870); Schl., Mus. Pays-Bas, vii., p. 34 (1876); Anderson, Zool. Res. Exped. Yun-nan, p. 39 (1878; with full synonymy); Hose, Mamm. Borneo, p. 12 (1893).