123 Mr. 0. Salvin on the Genus Cinclus. 



C fuscuSj capite et pectore albis : rostro nigro, pedibus 

 plumbeis. 

 Hab. Peru, province of Jauja {Tschudi) ; Bolivia {Mus. 

 Smithson.). 



13. Cinclus leuconotus. 



Cinclus leuconotus, Sclater, P. Z. S. 1857, p. 274, and Am. 

 Cat. p. 10, pi. 2, " Cinclus leucocephalus, Tsch.," Lafr., Rev. 

 Zool. 1847, p. 68. 



C. fusco-nigricans, dorso medio et capita toto cum corpore 

 subtus ad ventrem medium albis : pileo dorsoque fusco 

 variegatis : rostro nigro, pedibus obscure corneis : long, 

 tota 5'5, alae 3'8, caudse 1'6. 



Hab. Andes of New Granada, Pasto [Delattre) ; Ecuador, near 

 Quito {Mus. Jar dine). 



Mus. Brit, et P. L. Sclater. 



These two Andean species, as will be seen, differ widely 

 from any inhabiting the northern hemisphere. Though long 

 known, they are still quite rare in collections. 



It will be seen that I have in the above remarks considered 

 the geographical distribution and range of each race and 

 species of the greatest importance ; indeed, as ornithological or 

 any other biological science advances, it becomes more and 

 more apparent that accurate knowledge on this point is abso- 

 lutely necessary for the satisfactory establishment of species. 

 A difiFerence of habitat has almost come to be equivalent to a 

 distinctive character when accompanied with an actual slight con- 

 stant difference of form or colour. I believe that there is more 

 evidence to be obtained towards elucidating the problem of the 

 origin of species from close study of facts of geographical distri- 

 bution than from any other source. The attractions of such 

 study are manifest, and I would especially recommend it to 

 British ornithologists. Let them follow up the range of almost 

 any one of our common English birds, and they will be doing 

 good service. Even the House-Sparrow {Passer domesticus), 

 followed through all its local forms, would be most instructive; 

 but to do this they must extend their observations beyond the 

 limits of these islands. This, under all circumstances, is neces- 

 sary for attaining an accurate knowledge of our bird-fauna. 



