14 HISTORY AND PHYSIOLOGY. 



complete repose, and even sixteen hours of the 

 twelfth. Then she passes four days and one third 

 as a nymph. It is on the sixteenth day therefore 

 that the perfect state of queen is attained. 



The male passes three days in the egg, six and 

 a half as a worm, and metamorphoses into a fly 

 on the twenty-fourth or twenty-fifth day, after the 

 egg is laid. The great epoch of laying the eggs 

 of males may be accelerated or retarded by the 

 state of the atmosphere promoting or impeding 

 the collections of the bees. The development of 

 each species likewise proceeds more slowly when 

 the colonies are weak or the air cool, and when 

 the weather is very cold it is entirely suspended. 

 Mr. Hunter has observed that the eggs, maggots 

 and nymphs, all require a heat above 70 of Fah- 

 renheit for their evolution. The influence of tem- 

 perature in developing embryo insects is very 

 strongly illustrated in the case of the Papilio 

 Machaon. According to Messrs. Kirby and Spence, 

 "if the caterpillar of the Papilio Machaon be- 

 comes a pupa in July, the butterfly will appear in 

 thirteen days ; if it do not become a pupa till 

 September, the butterfly will not make its ap- 

 pearance until the following June." And this is 

 the case, say they, with a vast number of other 

 insects. Reaumur proved the influence of tem- 

 perature, by effecting the regular changes in a 

 hot-house, during the month of January. He also 



