THE KNTOMOLOGTST. 283 



in the year, in June and October : this circumstance has in- 

 duced an idea that the species is double-brooded, an idea 

 which is supported by the uuquestionable fact that the July 

 moths are the jnirents of the Octijber moths ; nevertheless 

 the i)heuomeuon is susceptible of another explanation : the 

 larvae bury ibeniselves, wheu full-grown, almost simultaneously, 

 at the end of July or in August; but thry undergo their fiual 

 change at very different dates : the greater number make 

 their appearance from the 1st to the 2(ilh of October, and 

 these, with rare exceptions, are barren females ; the abdo- 

 men is an euipty cylinder, containing neither eggs nor ovary: 

 one exception only has been observed, and that one is men- 

 tioned by Mr. Doubleday (Zool. 18()-2) : later than the end of 

 October the moths rarely a])pear, but nevertheless such is 

 occasionally the case, and in confinement I have known them 

 escaj)e from the pupa-case in November and December ; 

 several actually made their appearance on a Christmas day, 

 but 1 regret that these hybernal specimens were placed on 

 the setting-board without any observation being made on the 

 state of the ovary : Mr. Noye records (Zool. 1507) that he has 

 obtained moths on the 18th of April, 7th August, 8th Sep- 

 tember, and 25th September, but offers no remarks on the 

 slate of these specimens, which appear to have been caught, 

 not bred : the records of June captures are not only nume- 

 rons, but are most authentic, and it is quite certain that 

 during that month oviposition takes place, perhaps not ex- 

 clusively, but generally ; and all the females either bred or 

 captnred in June are abundantly prolific : finally, Mr. 

 Doubleday mentions (Zool. 1862) that he bred a barren 

 female which had been more than twelve months in the 

 puj)a. From a nuiltitude of records it appears that the 

 period of oviposition is June, of pupation August, and of 

 arriving at perfection June also, the disclosures in October, 

 November and December being imperfect and abnormal, and 

 the disclosures in April and May, if such take place, acci- 

 dental and exceptional : it is by no means improbable that 

 examplesdisclosedin the winter sometimes live until the follow- 

 ing Midsunnner. The moth is remarkable on many accounts: 

 its large size ; the singular representation of a death's head 

 on the thorax ; its fondness for honey ; and its power of 

 emitting a squeaking or creaking sound when handled or 



