300 UNGULATA 
particular species or variety of the group, and sometimes used in a 
generic sense to cover the whole. Although they were often com- 
pared by early writers to sheep, and spoken of as such, their affinity 
to the camel was very soon perceived, and they were included in 
the genus Camelus in the Systema Nature of Linneus. They were, 
however, separated by Cuvier in 1800 under the name of Lama, 
changed by Illiger in 1811 to Auchenia (in allusion to the great 
length of neck, adxjv), a term afterwards adopted by Cuvier, and 
almost universally accepted by systematic zoologists, although there 
has been of late a disposition to revive the earlier name. 
In essential structural characters, as well as in general appear- 
ance and habits, all the animals of this genus very closely resemble 
each other, so that the question as to whether they should be 
considered as belonging to one, two, or more species has been one 
which has led to a large amount of controversy among naturalists. 
The question has been much complicated by the circumstances of 
the great majority of individuals which have come under observa- 
tion being either in a completely or partially domesticated state, 
and descended from ancestors which from time immemorial have 
been in like condition, one which always tends to produce a certain 
amount of variation from the original type. It has, however, lost 
much of its importance since the doctrine of the distinct origin of 
species has been generally abandoned. 
The four forms commonly distinguished by the inhabitants of 
South America are recog- 
nised by some naturalists 
as distinct species, and have 
had specific designations 
attached to them, though 
usually with expressions of 
doubt, and with great diffi- 
culties in defining their dis- 
tinctive characteristics. 
These are (1) the Llama, 
Auchenia glama (Linn.), or 
Lima peruana (Tiedemann) ; 
(2) the Alpaca, 4. pueos 
Linn.) ; (3) the Guanaco or 
Huanaco, 1. huenacus (Mo- 
Fic. 116.—Head of Vicugna, from an animal living ru oe (4) the V aeenss 
in the Gardens of the Zoological Society of London. d. TLcUgna (Molina), or -d. 
vieunna, (Cuv.) The first 
and second are only known in the domestic state, and are variable 
in size and colour, being often white, black, or piebald. The third, 
and fourth are wild, and of a nearly uniform light-brown colour, 
passing into white below. They certainly differ from each other, 
