122 

 CHAPTER VII. 



Comparison between the patterns of caterpillars and those 

 OF THE Pupa, the Imago and of other Larvae of Insects. 



From early days the pupae of butterflies have had a great 

 attraction for the human mind. 



The word chrymli^ was already used by Aristotle to indicate 

 the goldcoloured pupae of some butterflies. 



The conception of the pupal-stage has not always remained the 

 same however. W. Harvey for instance considered the pupa to be 

 a perfect egg;. 



J. Swammerdam who was the first to discover the wing-rudiment 

 in the caterpillar, suspected that the pupa was not a new creation 

 but that the result of another moult (1737, Bihlia Naturae p. 567). 

 He attached much value to the fact, that the setae of the cater- 

 pillars also occur on the pupa. 



The majority of later investigators were convinced that the 

 caterpillar is the primitive state and the pupa a secondary pheno- 

 menon. When the Darwinian ideas gained ground, it therefore 

 became an important problem, how this resting stage had arisen. 



The first who tried to give a solution was John Lubbock (1871), 

 in a paper which became very popular. He thought that the pupa 

 was a form of transition between the larva and imago, necessitated 

 by the great difference in the mouth parts. I think that the con- 

 ditions of Micropteryx and Eriocephala definitely dispose of this 

 theory. 



Lubbock's opinion has been propagated by many treatises, but 

 from the first another view has maintained itself against it. 



Brauer (1869) defended the opinion that it is the larva which 

 has become modified and this conception has recently gained 

 ground again. 



Ivatzeburg's discovery of the external genital organs of the 

 pupae (1840) was not paid attention to at the time, and thus 

 it may be explained that Jackson and Poulton thought they 

 had described these organs for the first time (1890) after 



