40 BULLETIN 99, UNITED STATES NATIONAL MUSEUM. 
taken in August and is probably only about two or three months 
older. It was clinging to its mother when collected. A slightly 
larger young one, taken August 27, has the color almost exactly as 
in adult specimens but has shorter hair throughout. As is well 
known, the growth of young monkeys is very slow, and this specimen 
is probably about a year older than the two smallest animals men- 
tioned above. A young specimen, taken on October 14, with head 
and body measuring 370 millimeters, is, except for the less luxuriant 
tail plume, almost exactly like old animals. It is probably in its 
third year, although the first molar has not yet erupted. Doctor 
Lénnberg has written that the young of Colobus caudatus kikuyuensis 
differs from the young of C. c. caudatus of Kilimanjaro in color,} 
but it appears that this is not the case. Young monkeys grow so 
slowly, as compared with most mammals, that very slight difference 
in size indicates a considerable difference in age, and it is apparent 
that Doctor Lénnberg has compared, from the two localities, young 
specimens in a very different stage of pelage development. 
COLOBUS CAUDATUS PERCIVALI Heller. 
Plate 16. 
1913. Colobus abyssinicus percivali HELLER, Smithsonian Misc. Coll., vol. 61, No. 
17, p. 6. October 21. (Mount Gargues, British East Africa; type in 
U.S. National Museum.) 
Specumens.—Two, as follows: 
British East Arrica: Mount Gargues, north slope at 6,000 feet 
altitude, 2 (Heller). 
This subspecies is, according to Heller, confined to the forested 
summit of Mount Gargues, where it is rather rare. But one group 
of 15 or 20 animals was seen during his stay of a week on the northern 
peak. On Mount Gargues, August 29, 1911, Heller made the follow- 
ing entry in his journal of the Rainey Expedition: 
The colobus monkeys could be heard calling in the early morning, while it was still 
dark, and again about sunrise. They make a hoarse, growling bark which is often 
heard in the morning and during the night. None have been seen since I shot two 
out of a herd of fifteen or more on our way up the mountain, but they have been heard 
nearly every night. 
COLOBUS OCCIDENTALIS OCCIDENTALIS (Rochebrune). 
1887. Guereza occidentalis RocHEBRUNE, Faune Sénégambie, Suppl., p. 140. 
(Noki, ‘‘haut Congo” [?Angola]). 
Specimens.—Three, as follows: 
Ueanpa: Budonga Forest, 3 (Raven). 
These specimens are much like Colobus occidentalis matschier of 
Kavirondo but are smaller, with longer tails and smaller skulls. 
1 Kungl. Sv. Vet. Akad. Handl., vol. 48, No.5, p. 33. 1912. 
