Ornithology of the Cape Verde Islands. 279 



each, but four to six are the usual complements. For 

 Kestrels^ eggs, each clutch is remarkably uniform as regards 

 coloration. 



Strix insularis. 



We found this Owl by no means common. Holes in the 

 rocky sides of valleys and the tops of coconut-trees are chosen 

 as nesting-sites. On Dec. 2nd, 1897, while on Santiago, a 

 native brought me two young birds in down, which I managed 

 to bring home safely, and they are now in an aviary in my 

 garden. They seem very popular, for all the White Owls of 

 the neighbourhood pay them visits nightly, and no doubt 

 envy them for their choice food, which consists of five 

 Sparrows and three mice every night. 



The female of this species is decidedly smaller than the 

 male, and the breast-markings are fewer and less bright. 



Sylvia conspicillata. 



Breeds on Sao Nicolau in November. In the following 

 month we obtained several immature males on Santa Antao, 

 and their plumage resembled that of the adult female. 



Sylvia atricapilla. 



This Blackcap is a resident on the northern islands of the 

 archipelago. On Sao Nicolau in November it was breeding 

 in large numbers, and every valley was resounding with its 

 musical song. About the end of February the numbers of 

 the residents are increased by migrants. The nests were 

 built in the cofl'ee-bushes, and we obtained a fine series of 

 clutches. The eggs of only one of these approach in any 

 way the common type of our Blackcap's; all the others are very 

 light in ground-colour, blotched, spotted, and streaked with 

 dark and reddish brown, and underlying markings of purplish 

 brown, so as to form a zone round the larger ends. The 

 dimensions vary in length from 0"'8 to 0""73, and in breadth 

 from 0"-64 to 0"-5. 



Sylvia gularis. 



This subspecies of S. atricapilla, with the brown throat, 

 is to be found only on Santiago. Their numbers are, how- 



