INTRODUCTION. ZO 



of structure, these two groups are similar in their mode of life 

 and in their distribution. All those of which \ve have any know- 

 ledge are root-feeders during their larval life and leaf-feeders 

 when adult. The two groups occur side by side iu great abun- 

 dance of individuals and species throughout Africa, Asia, and the 

 islands of the Pacific, but without reaching Australia (leaving out 

 of account two or three ubiquitous species which have un- 

 doubtedly been transported by artificial means). Both groups 

 are absent also from the Pacific slope of South America; but, 

 while the ADOBETINI are completely unrepresented on the 

 American continent, the AyoMALiui are fairly numerous in its 

 warmer regions. It is probable that the single genus Anomala, 

 perhaps because a recently-evolved one and not yet split up into 

 any natural and well-defined subdivisions, outnumbers in species 

 all the other liUTEUNjB. 



The ADOHETIXI are rather small, brownish, pale or dull-coloured 

 insects of nocturnal habits, and frequently euter houses iu the 

 evening attracted by light. 



The ANOMALIHI also include many inconspicuous forms with 

 similar habits, but in the Oriental Hegion these are outnumbered 

 by brightly -coloured diurnal species some of them.amongst the 

 most brilliantly decorated of all known insects. Vivid green and 

 golden hues are very prevalent amongst them. 



In these two arboreal groups the legs and feet are formed for 

 clinging to the leaves and twigs amongst which the insects live, 

 and the mouth for a diet of leaves. Although so much alike "in 

 their mode of life and in many points of structure, the ANOMAI.INI 

 and ADOHETIXI are sharply divided by their method of feeding. 

 In the first the labrum and labium form a pair of horizontal lips 

 between which the jaws work, each pair co-adapted for grasping 

 and dividing the food like a pair of scissors. In the second group 

 the labrum is produced downwards across the mouth-opening, 

 which is more or less completely divided into a right and left half. 

 Although in the great majority of the species this bisection of the 

 mouth is complete, there are several small genera in which it is 

 in varying degrees imperfect, and in such forms as Prodorttus and 

 O.vi/adoretus there is an obvious approximation to the ANOMALIM. 

 According to the system of classification hitherto adopted that 

 devised more than half a century ago, when comparatively few 

 forms had become available for study, by the two highly competent 

 entomologists, Burnieister and Lacordaire these two groups have 

 been put at opposite ends of the subfamily and separated bv the 

 large, mainly American, group of the true BUTELLNI, of which 

 the PAKASTASIINI of this volume form a small part. I have 

 ventured to depart from this system, and to put the latter group, 

 which is undoubtedly the one with the nearest relationship to the 

 DYJ. T ASTINJE (omitting the aberrant genus Peltonotus), at the 

 beginning of the subfamily, thus bringing near together the 

 AKOMALIXI and ADOEETLNI. As a connecting-link between 

 these stands the new tribe AUOIUIHIXYPTUKI, which I have 



