APPENDIX 



Methods of Breeding Drosophila 



Drosophila ampelophila has shown itself to be so 

 generally useful for class work in genetics and is 

 being so widely employed for this purpose that it 

 may not be out of place here to give a few directions 

 concerning apparatus, methods and material. 



Culture Bottles. — ^I^arge-mouthed bottles of 

 about 500 c.c. capacity should be used. Pint milk 

 bottles can be purchased at reasonable rates from 

 wholesale dealers, and serve admirably as culture 

 bottles. Stoppers of raw cotton are used, which 

 should be tight but not packed in the mouth of the 

 bottle. 



Temperature. — The optimum is about 25° C. 

 Extreme summer heat kills the flies in culture bottles 

 unless special precautions are taken. Cold retards 

 the development of the larvse indefinitely, but the 

 flies themselves can withstand almost a freezing 

 temperature. Ordinary room temperature suffices, 

 as a rule, but a controlled temperature of about 

 25° C. is better. 



Food. — Ripe fermented banana is the best food. 

 If raw bananas with intact skin are peeled and put 

 into old juice contamination is not likely to occur, 

 but for ordinary purposes the bananas should be 



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