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hibernating stage comparable to that referred to above assumed 

 during the first winter. 



Then we have the large number of insects that hibernate in 

 the pupal state. As in the case of those hibernating in the egg, 

 development may be delayed by the winter until the following 

 spring, or it may be already complete before winter supervenes. It 

 is well known, for instance, that the moths of the Small Eggar are 

 ready formed within the pupa; in the autumn, but they do not 

 emerge until the February following. This same species is a good 

 example of a similar phenomenon to that we saw in the Zyijaena 

 larvae, viz., what is Imown to lepidopterists as " lying over." Not 

 all the moths of a brood will emerge when their time is due, but 

 many of them will remain over for another year, or even two or 

 more years before emergence. This behaviour is not dependent 

 upon the meteorological conditions at the time of year the species 

 is due to emerge. If the pupas of a brood that have been reared 

 all together under precisely similar conditions be examined in the 

 autumn, some of them will be found to be dark coloured, with the 

 markings of the moth plainly discernible through the pupal sheath. 

 Others will be seen to be pale, greenish-amber coloured, and evidently 

 quite undeveloped. From the former the moths will emerge the 

 following spring, or if, for any reason, such as unfavourable 

 weather at the time, they fail to do so, they will perish without 

 producing moths." The undeveloped pupae remain without change 

 until the following summer, when in some or all of them develop- 

 ment will take place, and the moths emerge the February following. 

 Probably, however, some will still remain unchanged to produce 

 moths the third or fourth February after their larval period. What 

 are the factors that determine whether development shall proceed 

 or be postponed is a complete mystery, but obviously this "lying 

 over " IS a means of providing against the extinction of the species 

 in case of unfavourable conditions supervening at the time of year, 

 in any case very undependable, when the species is due to emerge. 



Finally, we have those insects that pass the winter in the 

 perfect state. Disregarding for the moment those truly winter 

 insects that only attain the perfect state, and pair, oviposit and die 

 all within the winter months, which for the present purpose may 

 be regarded as divided between the late autumn insects that pass 



* South tajs that it is the moth ready formed within the pupa that lies 

 over until the following year, but in my experience this is not so. 



