8 Allen's naturalists library. 



allied 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. toi'quatits, 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 

 t ) 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, xvhich 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. 

 sliawi) 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. semitorquaiits^ 

 from Dzungaria, being apparently shut off by high mountains 

 and impassable deserts. It must, however, be added that 

 there can be no doubt that P. moJtgoUais, which ranges along 

 the valley of the Syr-Darya, does occasionally interbreed with 

 P. chrysouielas from the valley of the Amu-Darya, for we have 

 seen a wild hybrid shot at Nukus w^hich 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 



