Packaku] insects of the GARDEN. 9 



both sexes, while the autumnal brood is composed exclu- 

 sively of females. Again in some species of moths where the 

 two sexes are of equal abundance Von Siebold found that it 

 Avas no unusual thing for individuals to be hatched from eggs 

 known to be laid by a previous virgin generation. 



Fairly entered upon the duties of active life the young 

 larva is capable of doing wonders in gastro-dynamics. It 

 would seem with most insects as if all the eating for their 

 lives were concentrated into this stage of their existence. 

 For there is a period coming of long cessation from activity, 

 when, in external immobility and seeming lethargy, wonder- 

 ful transformations pervade nei've and muscular tissues ; a 

 new body, wonderfully differentiated for a new existence in 

 a far more extended sphere than formerly, is taking on its 

 form beneath the rough and often unsightly pupa. 



After the last moulting the power and desire of eating are 

 lost, increased stores of fat are laid up for the sustenance of 

 the pupa, and the wings and legs of the future fly are forming. 

 The worm seeks a shelter and often spins a cocoon of silk, 

 and there, in quiet and away from the light, its functious of 

 animal life suspended and a very slow vegetative existence 

 barely sustained, as a chrysalis the insect spends a portion 

 of its life. 



The knowledge of the fact that all animals pass through 

 some sort of a metamorphosis is very recent in physiology ; 

 moreover the fact that these morphological eras in the life of 

 an individual animal accord most unerringly with the grada- 

 tion of form in the type of which it is a member, was the 

 discovery of the eminent physiologist Von Baer. Up to 

 this time tlic true significance of the luxuriance and diver- 

 sity of larval forms had never seriously engaged the atteu. 

 tion of systematists in entomology. 



What can possibly be the meaning of all this putting on 

 and taking off of caterpillar habiliments, or in other words 

 the process of moulting, with the frequent changes in orna- 



9 



