21 2 



GUYER. 



[Vol. II. 



alba). Most authorities place the latter form in the same species 

 as the former. The immediate progeny of the pair just men- 

 tioned was always brown in color, the male being generally of 

 a slightly lighter shade than the female. 



When these doves of the second generation bred they 

 brought forth young which seemed usually to revert to the 

 ancestral type ; one member of the resulting pair was generally 

 white, and the other brown. Curiously enough, out of some 

 eighteen birds of this generation that I killed, the brown ones 



Fig. I. — A diagram showing the lineage of the dove under discussion. 



were invariably male and the white ones female. In one case 

 where both of the young birds were brown, they were male, and 

 in another where they were white, both were female. 



Schematically, the lineage may be represented as in Fig. i. 

 The ancestral pair, one brown and one white, are represented 

 by the two enclosed circles to the left. They give rise to a 

 number of offspring, one pair of which is indicated by the 

 two enclosed dark circles to the right of the first. These, 

 breeding again, bring forth a large number of pairs, of which 

 one member in each pair is usually white, the other one brown. 

 The bird under discussion was of this last or third generation. 



From the beginning she seemed to be abnormal. She was 

 always of a very nervous disposition, and would fly wildly about 

 when her cage was approached. While under observation she 



