4 Journal New York Entomological Society. [Voi. vii. 



not more than ten species were known from Southern California, but 

 careful collecting in recent years by Messrs. Coquillett, Van Dyke, 

 Fenyes, Daggett, and the author, make it possible to say that fully 

 thirty species, or nearly half the number in our entire fauna, are now 

 known from the same region, and it is probable that further explora- 

 tion will add to this total. In the notes following the tables reference 

 will be made in the case of each species to the place of original de- 

 scription ; for complete bibliography the student is referred to the 

 revision of Dr. Horn. For a cabinet arrangement it would be better 

 to follow the order in which the species are mentioned in the notes, 

 rather than in the tables. 



It only remains to express my grateful appreciation to the friends 

 and correspondents for the generally hearty response to a:ll calls for 

 specimens or information. I have thus been privileged to study a far 

 larger material than any previous student has been able to command, 

 while the courtesies extended by the California Academy of Sciences, 

 the American Entomological Society of Philadelphia, the Museum of 

 Comparative Zoology at Cambridge and the National Museum have 

 enabled me, by the examination of all the types of Leconte and Horn, 

 to speak with more of authority than would otherwise have been pos- 

 sible. As might be expected, there remain in the material before me 

 sundry specimens — mainly uniques — which I have left unplaced. 

 The proper disposition of such as these, and the precise definition of 

 the limits of the species in the neighborhood of acuta and subbalteata 

 must be left to the wider view and larger experience of the future in- 

 vestigator. 



The table given by Dr. Horn for the separation of the genus into 

 groups, is, with some modification, given below : 



Elytral intervals 3-5-7 costiform, from narrow, agriloid 2 



Elytra with never more than a single interval distinctly costiform in more than 

 basal half, usually entirely devoid of cost;^^, form broader, usually more or less 

 depressed i 



1. Front margin of prosternum retracted, side not reaching the front angles. 



Prosternum trisinuate in front Acm^oder^ sinuat.^. 



Prosternum scarcely sinuale in front, the margin nearly straight or feebly arcu- 

 ate from side to side Acm^oder^ emarginat^. 



^Front margin of prosternum, not or very slightly retracted, usually straight 



ACM.-EODER.^ TRUNCAT.T.. 



_. Front margin of prosternum lobed at middle, sides attaining the angles 



ACM.EODER.^s LOBAT.^. 



2. Front margin of prosternum sinuate or lobed, tarsi unusually long 



ACM.qjODER.^i GRACII.I FORMES. 



