478 University of California Publications in Zoology [Vol. 11 



Albinism 



No cases of albinism in the meadowlarks received in the 

 laboratory have been noted. Variations in the amounts of black,- 

 yellow, and white markings have been noted, however. Speci- 

 mens received from the northern coast region have been the 

 darkest in color, those from the southeastern arid regions the 

 lightest in color. 



Abundance of the Different Sexes and of Juveniles 



If the numbers of the sexes collected is any criterion of their 

 comparative numbers, it miist be conceded that males are more 

 abundant. Fifty-eight per cent of one thousand birds received 

 from ten different localities were males. Collectors usually ob- 

 tained a larger percentage of males the first few months. This 

 can be explained on the grounds that the male is a larger and 

 more conspicuous bird. Then, too, it is the bird most often seen 

 during the nesting season. 



About seventy per cent of the birds collected during the 

 summer months were juveniles. This must correspond, to some 

 extent at least, with the comparative numbers in the field. 



Incubation and Moult 



If judged by the condition of the feathers on the breast, 

 females do most of the incubation. Breeding males were noted 

 as early as late February and as late as August. 



None of the birds has been largely denuded of feathers even 

 during the moulting period. At no time do they appear to be 

 greatly hindered by moult. 



Effect of Systematic Destruction on Numbers 



A systematic destruction of birds having been carried on in 

 connection with this investigation, there appeared an opportunity 

 to obtain evidence as to the result which might be expected as 

 regards a decrease in numbers. Consequently a letter was written 

 to deputies enquiring whether there had been a perceptible de- 

 crease in the numbers of birds in the localities where collections 



