symmetrical, scarcely capable of movement and not cleft, except 

 upon the front feet of certain males. The labrum of the DYNASTLN^E 

 is reduced to a thin membrane in the roof of the mouth and 

 is not visible without removal of the jaws. The forms which 

 connect the two subfamilies are natives of Australia and Tropical 

 America, which areas, directly connected in early Tertiary times, 

 may probably be regarded as representing the place of origin of 

 both groups. 



In his great work on the classification of the Coleoptera 

 (' Genera des Coleopt^res '), Lacordaire gave as the only rigorously 

 distinctive character of the EUTELIN.S; " les trois dernieres paires 

 de stigmates abdominaux divergeant fortement en dehors," in 

 contradistinction to the MELOLON THINGS in which those spiracles 

 are " divergeant fftiblement de dedans en dehors." This antithesis,. 

 first enunciated by Erichson in his ' Naturgeschichte der Insecten 

 Deutschlands/ has since been repeated by various eminent author- 

 ities without explanation, although Sharp, in the Cambridge 

 Natural History, has altered the formula to "abdominal spiracles 

 placed almost in a line " (MELOLONTHINJE) and " abdominal spi- 



th 



racles placed in two lines " (ETTTELIN^). In both forms the 

 exact meaning of the phrases is difficult to grasp, even when actual 

 specimens are compared. The meaning I believe to be, as I have 

 expressed it in my previous volume, that in the EUTELIN.E the 

 posterior spiracles of the two sides are placed in two strongly 

 diverging lines, while in the MELOLONTHHST^; they form scarcely 

 diverging lines. Attempts to apply this generalisation have 

 proved unsuccessful, and I have been obliged to abandon it as of 

 no real value. Many differences occur in the position and relative 

 sizes of the spiracles, but these do not indicate any natural line 

 of cleavage, as supposed by Erichson and his successors. For 

 many genera the formulae given above are correct, but they are 

 certainly not of general application. In the Euteline genus 

 Lagochile, for instance, the spiracles are almost in a straight line, 

 while in Hoplla the line formed by them bends outwards as 

 strongly as in any Euteline I have examined. It is doubtful 

 whether Lacordaire's criterion has ever served for the actual 

 resolution of any doubtful case, and probably the great authority 

 rightly attached to his name is the chief reason for the long- 

 continued repetition of a useless formula. 



The structure of the claws is really sufficient to distinguish the 

 EUTELINE, not only from the DYNASTIIO; but from all other 

 related groups. In the typical MELOLONTHIN^E the claws are all 

 alike, quite symmetrical on each foot, and not separately, if at all, 

 movable. In rare instances (e. g. Cyphonoocia) there is asymmetry, 

 but not inequality in length, in those of the male and in a few 

 cases (e.g. Plectris) there is a slight inequality in each pair of 

 claws, but (unlike any Euteline) the shorter claw is cleft like 

 the longer. The HOPLIINJE have sometimes, like the EUTELIWJE, 

 very mobile and dissimilar claws, one claw in some cases having 

 disappeared altogether from the hinder pairs of legs, but here 

 again both, if any, are cleft. This group, however, is so distinct 



