29 ) 



IV. Practical suggestions and enquiries as to the method 

 of breeding Selenia illustraria for the purpose oj 

 obtaining data for Mr. Galton. By Frederic 

 Merrifield. 



[Read February 2nd, 1887.] 



It being necessary for the purpose of these experiments 

 to bring up in a healthy state nearly all the individuals 

 in every successive brood, instead of merely to obtain a 

 fair number of cabinet specimens, — the usual object of 

 larva-breeders, — more than usual care will be necessary 

 to avoid dwarfing and casualties. No apology, there- 

 fore, is offered for submitting the following detailed 

 suggestions, — the result of answers kindly given to 

 many enquiries, — while at the same time further 

 information is invited. 



Selection of Species. — The species chosen should be 

 variable in size and easy to rear, pair, and measure ; 

 and regularly double-brooded species have the great 

 advantage of reducing by one-half the period required 

 for bringing the experiments to an end. After fully 

 weighing objections, the writer has determined to try a 

 species of which he has considerable knowledge, Selenia 

 illustraria (the Purple Thorn), adding to his preliminary 

 experience by practising on the common S. illunaria, 

 which appears a month earlier. Other double-brooded 

 species are recommended, viz., the Ephyras (especially 

 E.pendularia), Drepanafalcula, and the Closteras; among 

 single-brooded moths some of the common and easily 

 bred Bombyces, especially Hypogymna dispar, and that 

 variable, interesting", and easily reared Geometer, 

 Angerona prunaria. Those who can get over the diffi- 

 culty of pairing which the butterflies generally present 

 would probably find the common and easily fed and 

 double-brooded Pieris brassicce very suitable. 



It is much to be desired that the same species should 

 be taken up by more than one observer, as in this way 

 the accidental failure of a brood may be guarded against, 



TRANS. ENT. SOC. LOND. 1887. — PART I. (APRIL.) 



