72 



Zbc lllse of 36irD5 in Bionomical 

 lEyperinients. 



By F. Finn, B.A., F.Z.S., M.B.O.U. 



[Reprinted, by permission, from the Field for April 29th, 1905, 



P- 725]- 



LTHOUGH from the point of view of the 

 l)ionomical experimenter birds possess one 

 great drawback, in the fact that in most cases 

 it is impossible to obtain more than one 

 generation from them annualh% they have sufficient 

 recommendations to be more utilised by philosophical 

 naturalists than is at present the case. 



A public aviary might be stocked with useful 

 scientific material and yet be made attractive, while 

 the progeny reared from them may often be advan- 

 tageousl)'' disposed of when they have served their 

 purpose, thus reducing the cost of experiments. 



Our British species are not, generallj^ speaking, 

 good breeders in captivity, or bionomicalh' interesting, 

 so that, although often very cheap, they are not 

 always suitable for scientific use. I propose here- 

 inafter to deal chiefly with some foreign species which 

 are easily obtainable and maintained without difficulty. 

 All will winter out of doors in a well-sheltered aviary 

 without artificial heat, provided they are turned out 

 when the .spring is advanced enough to enstire genial 

 weather. 



The Budgerigar or Undulated Grass Parra- 

 KEET (^Melopsittaais imduiaius) is an excellent bird for 

 bionomical investigation. It is familiar to most 

 people, even those not interested in aviculture, as 

 l^eing commonly employed as a "fortune-telling bird" 

 in the streets. The type is barred yellow and black 

 above, and grass green below, but a domestic variety 

 is not now uncommon, in which the general plumage 

 is yellow, with the markings faintly discernible. This 



