IXTRODrCTION, 1>1 



really competent writers like Buriiiei.ster, it has been the usual 

 custom to describe species from one sex only, generally without 

 the describer liimself luiowino; which. 



One of the instances just referred to is Aaomala Inlunala, Tairn). 

 (figs. 36 & 37) aniline which indicates the very distinctive pattern 

 of an insect bearing two pale crescent-shaped marks upon a dark 

 background. But the describer was not aware that he was deahng 

 with the male only, which sex appears to be less abundant than 

 the other. I have seen only thi-ee or four specimens of it, but 

 more than a dozen females, and the latter are pale-coloured insects 

 with a dark crescent, and, of course, present an appearance in 

 very marked contrast to the male. A similar difference occurs 

 in A. nigrovaria. 



In Anomala fulviveutfis, an insect most perplexingly variable 

 in its colouring, the males are nearly always of a deep metallic 

 green on the upper surface, often with a yellow margin to the 

 pronotum ; while the females may be yellow, their elytra may be 

 striped with green or entirely green, and the pronotum usually 

 bears two green spots, which may coalesce ; but I have not yet 

 seen any female quite as dark-coloured as the lightest males. 

 A. cJiinensis is a closely-related, but much more constant, species ; 

 and here, while the female has the head and pronotum red and 

 the elytra only dark green, the male has the forehead and middle 

 of the pronotum, as well as the elytra, green. 



In A. coiijur/a the pattern is the same in both sexes, but the 

 decorated areas are of a much lighter colour in the female than in 

 the male. 



These examples illustrate the general rule that when a differ- 

 ence of coloration occurs between the two sexes the male is the 

 darker coloured form. In the Parastasia group, however, this 

 rule is reversed, and we find the darker coloration an invariable 

 indication of the female. In several species that sex is entirely 

 black, while the male is yellow, and in the Indian species, P. anda- 

 manica and P. coiijiuens, the females have a ground-colour of black 

 or very dark brown, while in the males it is yellowish, the markings 

 being the same in both, 



Jfabitg and 3Ietamorjy7ioses. 



Very little has yet been recorded as to the life-history and 

 early stages of the Rutelinje. The lai-va of Parastasia eonjfaentt 

 has been described and tigured by Schiodte (Naturhistorisk 'J'id- 

 skrift (3) ix, 1874), and Mr. H. Maxwell Lefroy has published 

 descriptions and figures of uinomalav avians, one of the counnonest 

 Indian species, in all its stages (Memoirs of the Indian Depart- 

 ment of Agriculture, Entom. «er. ii, 8, 11)10, p. 143, pi. xiv). 

 More recently Mr. F. H. Gravely has found two species of Adoretus 

 in all stages, so that the larvae of the three principal types of Indian 

 RuTKLix.E have now been discovered. They are identical in all 

 essential tratures, ajid dilfer only in slight details from the larvifi 



