2 ARKIV FÖR ZOOLOGI. BAND 14. N:0 25. 



to obtain a fair view of the zonal distribution of the differeiit 

 species represen t ed. It is, of course, evident that such beings 

 as birds, which have so great faculty of locomotion, do not 

 need to remain in the same district, even if they are not migra- 

 tory, and it is also clear, that they in many instances move 

 from one place to another in order to get better access to some 

 kind of food. In one instance it is even plainly stated on the 

 label, that a species (Chamaepetes goudoti), usually lives at 

 a certain altitude, but that it, when the berries and fruits at 

 a higher altitude are ripe, wander up to this to enjoy the 

 »set table». There might probably be several such instances 

 or analogous cases, and many birds are certainly very inde- 

 pendent of the altitude, if they only find their necessities of 

 life, as for instance several water birds and birds of prey. 

 But on the other hand there are certain general rules for the 

 zonal distribution of the bird-life as well as for other living 

 beings. This has been admirably proved by Frank M. Chap- 

 MAN in his splendid work »The Distribution of Bird-life in 

 Colombia» (Bull. Amer. Mus. Nat. Hist., vol. XXXVI, 1917) 

 and also »The Distribution of Bird Life in the Urubamba 

 Valley of Peru» (U. S. Nat. Mus. Bulletin 117, 1921), not to 

 speak of others. The author quoted has also had the opportu- 

 nity to study the biologi cal conditions on the spöt and thus 

 to get a clearer conception of many things, than ever can be 

 acquired by naturalists, who only are able to work on material 

 collected by others, how valuable in itself this may be. In 

 consequence of this there must be many short-comings in 

 the following attempt to give a review of the distribution of 

 the bird-life in those parts of Ecuador, to which the collection 

 ref ers. The ornis of the tropical belt is not by far so completely 

 represented as could be wished for, and also the specimens 

 from the eastern side are not numerous enough to give a 

 satisfactory view of the fauna there. Nevertheless we have 

 decided to set forth the following survey, which, in spite of 

 its incompleteness, must be regarded to throw some light över 

 the distribution of the birds in certain interiör parts of Northern 

 Ecuador. 



In the following we have accepted the usual scheme of 

 division of the different life zones. Thus the tropical zone 

 from sea level to an altitude of approximately 5000 feet. Ac- 

 cording to a communication of Mag. Heilborn this nearly 



