g LLOYD’S NATURAL HISTORY. 
aliied forms without white collars, or with only traces of 
this ornament, occur south of about 35° N. lat. and east 
of about 90° E. long., while of the ringed form of this 
section, P. forgwatus, though it is found in China as far south 
as Canton (and a slightly different form occurs in Formosa), 
ranges far north to the Lower Amoor, and a _ paler represen- 
tative is met with to the north of the Nan-shan Mountains, 
which lie north of 35° N. lat. So, on the whole, we may 
regard the ringed form as the northern, and those with- 
out a ring, as the southern type; and it seems reasonable 
to suppose that all the species have probably sprung from an 
ancestral ringed form of northern origin, and that the occur- 
rence of a partial white ring in certain individuals of the 
southern species, which are normally devoid of this ornament, 
is due to the fact that they still occasionally revert to the 
original stock. It is quite wrong to regard such partially ringed 
individuals as hybrids, for in most cases the country which 
each species inhabits, is effectually shut off by enormous ranges 
of mountains, which completely bar all intercourse between 
the ringed species and their southern allies. For example, it 
is not uncommon to find examples of Shaw’s Pheasant (P. 
shaw?) from the valleys of Yarkand with an imperfect white ring 
round the neck ; and it is practically impossible for this species 
to meet with any of the ring-necked forms, P. semtorguatus, 
from Dzungaria, being apparently shut off by high mountains 
and impassable deserts. Jt must, however, be added that 
there can be no doubt that P. mongolicus, which ranges along 
the valley of the Syr-Darya, does occasionally interbreed with 
P. chrysomelas from the valley of the Amu-Darya, for we have 
seen a wild hybrid shot at Nukus which is beyond doubt 
a cross between the two forms. In this instance, however, 
there is nothing to prevent the ranges of the two species from 
coalescing, and no doubt the ring-necked P. mongolicus occa- 
sionally finds its way south along the Eastern shore of the 
Aral. Any two species of this genus will interbreed freely 
