334 ) COLEOPTERA OF NORTH AMERICA. 



Tlie antennae are longer than the body in both sexes; pilose 

 in Methia, sparsely filiate in the other genera. 



Antennje with 2d joint distinct. 2. 



Antennae with 2d joint obsolete (therefore apparently 10-jointed). 3. 



2. First joint of antennae with a small apical spine, front larger and more 



vertical, eyes more separated. Idcemea. 

 First joint of antennae with a stout spine, front short, eyes approxi- 

 mate. Styloxus. 



3. Eyes emarginate. Methia. 

 Eyes' divided. Dysphaga. 



Methia pusilla Newman, occnrs in the Southern States; Dyx- 

 phaga tenuipes (% ventralis) Hald., in Pennsylvania, in hickory 

 twigs, D. Isevis Lee., in Illinois; they are similar in size and 

 form, but the prothorax is coarsely and densely punctured in D. 

 tenuipes, while it is shining and only sparsely punctured in D. 

 Isevis. 



Styloxus is founded on a species from Lower California, some- 

 what larger than Methia pusilla, but also of a uniform bfowu 

 color. Idcemea is established on a much larger Texan species. 



Fam. lyl— chrysomelidae. 



Mentum not inserted upon a peduncle, usually transverse, 

 and not large; ligula usually coriaceous and entire, though 

 sometimes membranous and bilobed; labial palpi 3-jointed. 



MaxilUe exposed at the base, feebly developed, bilobed; 

 palpi -i-jointed, cylindrical, usually not slender, but rarely 

 dilated or elongate. 



Head either prominent, or concealed under the shield-like 

 prothorax (Cassidini); epistoma usually distinct and well 

 separated; eyes entire, or emarginate on the inner side, finely 

 granulated ; mandibles short, robust (larger in some Clyth- 

 rini); labruni transverse, usually rounded in front. 



Antennas variable in position and form, usually 11-jointed, 

 filiform, serrate, or somewhat clavate; outer joints from 

 5-11 (Donaciaa) covered with sensitive surface. 



Prothorax usually margined at the sides, but not in cer- 

 tain tribes; side pieces not separate in our genera from the 

 prosternum; coxal cavities open or closed, contiguous or 

 separate; prosternum not prolonged. 



Mesosternuni narrow or wide; side pieces attaining tlie 

 coxte. 



