1920.] Birds of the Canary Islands. 551 



Whether altitude is indirectly responsible for the Blue 

 Chaffinch {Frin(/illa teydea teydea) and the Woodpecker 

 [J >njobates major canariensis), which inhabit the pine forests 

 of Tenerife at an altitude of from 4000 to GOOO feet, differing 

 in minute but perfectly distinct points from the corre- 

 sponding subs[)ecies Fr/iujil/a teijdea yohitzeki and Dri/obates 

 major thaaneri inhabiting the pine forest of Gran Canaria, 

 which are found at a lower altitude of from 3000 to 4000 feet, 

 it is beyond my power to say. The pine forests o£ Tenerife, 

 through more often being in heavy cloud than the Pinar of 

 Gran Canaria, are probably damper than those in the latter 

 island, but of the two forms the Gran Canaiian race is 

 decidedly duller in general colouring than the clear blue 

 Tenerifian bird, and this brings us to the striking effect 

 Avhicli Climate and Light can have on, at any rate, the 

 plumage of a l)ird. 



That Quails are affected to a very marked extent l)y the 

 degree of moisture in the atmosphere was instanced at a 

 former meeting of the British Ornithologists' Club, when it 

 was shown by Mr. Ogilvie-Grant that in a large series of 

 Bastard Quails, ranging from India to the Loo Choo Islands, 

 the amount of rainfall in the various districts could be fairlv 

 accurately estimated from the colour of the plumage of the 

 Quails. It is undoubtedly the dry desert climate of Fuerte- 

 ventura ami Lanzarote which is responsible for the pale 

 plumaged birds found in those islands, of which a list has 

 already been given. 



The air in these islands is remarkably clear, the light 

 extremely bright, and as Colonel Meinertzhagen remarks in 

 iiis thoughtful paper on " Geographical Distribution and 

 Migration" (Ibis, 1919, pp. 379-392), from observations in 

 Palestine and elsewhere, '• a higli temperature, a dry atmo- 

 sphere, and a bright light seem to produce tliat bleached 

 effect usual in desert forms." What better instance of this 

 can be quoted than that of the Fuerteventuran and Lanyarote 

 Titmouse {Parus cceruleiis degener\ see Plate XV'. fig. 1, 

 when compared with the Titmice inhabiting the higher, 

 tnoister, and more verdant ishmds of the western Canaries, 



SER. XI. VOL IJ. 2 P 



