FIELD BOOK OF INSECTS. 



all of which have the tips of the elytra simple, and the 

 tarsi dilated, spongy beneath. With the exception of this 

 genus, the Northeast has only H&monia nigricornis, 

 which has narrow tarsi and a distinct spine at the outer 

 angle of each elytron. Adults of Donacia rarely enter the 

 water, except to lay eggs, but those of Hamonia are more 

 aquatic. 



Sagrini 



In addition to the characters given above, members of 

 this tribe may be recognized by their first ventral, abdomi- 

 nal segment being not much longer, if any, than the two 

 following ; tarsal claws cleft or toothed and ely tral punctures 

 irregular (not in rows). Our only common species is 

 Orsodacna atra. The sides of its pronotum are rounded 

 and have neither tooth nor tubercle in distinction from 

 Zeugophora (outline of eyes indented) and Syneta (outline 

 of eyes not indented). Its color is so variable that seven 

 or more named varieties are recognized. It may be 

 practically all black, or the pronotum and elytra may be 

 reddish or yellowish, variously spotted or striped with 

 black. It is about .25 in. long and is often abundant on 

 willow and other very early blossoms. 



Criocerini 



Members of this tribe may be distinguished from the 

 Sagrini by their simple claws and their elytral punctures 

 being in rows. There are two genera: Lema, in which the 

 pronotum is constricted at about the middle, and Crioceris, 

 in which it is not. 



The most frequently noticed species is 

 trilineata. It is sometimes called the Old- 

 fashioned Potato-beetle because it was at work eating 

 potato leaves before the Potato-beetle came north and east. 

 It usually lays its eggs along the midrib of a leaf, not in a 

 cluster but at random. Its larvae have a curious, but 

 not unique, habit of piling their excrement on their backs. 

 Pupation takes place underground. The adult is shown 



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