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ART. XVIII. — Synopsis of the Melolonthid^e of the United States. 

 By John L. Le Conte, M. D. 



The Melolonthidse form a group of the family Scarabseidae less distinctly defined 

 than any other in that extensive family ; connecting with several others, it seems to 

 be the great central group, and embraces genera of such diverse form and structure, 

 as to render the attempts at classification not altogether satisfactory. Erichson was 

 the first to attempt a general arrangement of the tribe, and Lacordaire, while following 

 nearly in his path, has introduced some important changes. It would ill become me, 

 having studied only a fauna limited in genera of this type, to pronounce upon the 

 value of the affinities thus displayed between genera which I have never seen ; but I 

 have found great difficulty in placing in the schemes of those authors a new genus, 

 which should evidently have place within the limits embraced by them. 



The classification of Burmeister is founded upon entirely different characters, and 

 seems at first to give much more natural groups than those formed by Erichson and 

 Lacordaire, though the characters used seem by no means distinct or easy of applica- 

 tion. The great stumbling point in both systems is however the curious mixture of 

 characters found in the allied group Anthobia of Burmeister, part of which forms 

 Erichson's family Glaphyridse, enrolled in the great series of Scarabsei laparosticti. 

 Burmeister having examined (Lamell. 2, 2d, 467) the position of the abdominal stig- 

 mata in the genera of Erichson's Glaphyridse, found great variations between the 

 individual genera, some having them as in Melolonthidse, while in none had they 

 exactly the situation in which they are found in the other groups of Laparosticti. 

 From these facts he draws the inference that the family Anthobia as established by 

 him is a natural one, osculant between the Phyllophaga (Melolonthidse and Rutelidae 

 of Erichson) and Melitophila (Cetoniadae of Erichson), entirely denying the relation- 

 ship with the Laparosticti. 



While admitting the probable justice of the latter result, although Erichson notes 

 the transition from Phsenognatha to Hybosorus, I must say that the facts seem to me 

 to bear a very different interpretation. Looking for example at the four primary 

 groups into which Erichson divides the. Scarabsei pleurosticti, the reader will see that 

 the Melolonthidse have the posterior stigmata diverging but feebly, while the three 

 others have them diverging strongly. We will afterwards see that the position of 



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