The Origin of the Markings of Caterpillars. 2 1 3 



the ring-spots increase also in distinctness from 

 the tail to the head. 



Fifth Stage. 



The two specimens just mentioned, after moult- 

 ing, acquired the well-known markings of the adult 

 caterpillar already briefly described above. The 

 fifth is the last stage. 



The larva is known to occur in several variations, 

 Rosel having figured it in three forms ; light green, 

 olive-green, and dirty yellow. It has not been 

 since considered worth the trouble to attend to 

 the subject of caterpillar coloration. Thus, Wilde, 23 

 in his well-known work, takes no notice of Rosel's 

 observation, but simply describes the caterpillar 

 of Galii as " blackish olive-green." 



Having had an opportunity of observing twenty- 

 five adult specimens of this somewhat scarce 

 species at one time, I am able to state that it is 

 not in this instance di- or polymorphism, but a 

 case presenting a great degree of variability, with 

 which we have to deal. There are not several 

 sharply-defined types of coloration; but the 

 extremes are connected by numerous intermediate 

 forms. The extreme forms, however, certainly 

 preponderate. 



I have never met with Rosel's light-green form ; 

 neither was there a dark-green specimen among 



23 " Die Pflanzen und Raupen Deutschlands." Berlin, 1860, 

 P- 83. 



