CIIRYSOMELinAE. 345 



Group I. — Timarchae. 



This group is represented by two species in Oregon, extending 

 into California and British Coknubia. They are oval, convex, 

 black, or slightly bronzed insects of coarse scnlpture, and are easily 

 known by the very short nietasternuni, the absence of wings, and 

 the closed front coxal cavities. Timarcha inlricala has been 

 reported as extending to Western Kansas, but the locality needs 

 confirmation. The genus is well represented in Europe and Asia. 



Groui) II. — Entomoscelides. 



The body is elongate-oval, winged, with long metasternnm and 

 closed front coxal cjivities ; the tibite are gradually, but not 

 strongly dilated at the tip, and the outer face is deeply concave, 

 and the distal edge is obtusely angulated ; the claws are simple. 



One species, E nlomoacelis adonidifi, extends through the boreal 

 parts of both continents. It is black, with the upper surface in 

 great part brownish-yellow, with the middle of tlse prothorax, a 

 lateral dot, a wide elytral stripe and the suture black; the elytra 

 are densely rather finely punctured. 



As the preceding group tends towards certain apterous species 

 of Chrysomela, so does the present to other forms of the same 

 genus, and to Plagiodera. 



Groui> III. — Chrysonielae. 

 The species of this group are easily recognized by the meta- 

 stertium, which is at least as long as the 1st ventral segment, 

 even in the apterous forms which inhabit high mountain regions; 

 the claws are simple; the sides of the prothorax are sometimes 

 thickened, sometimes not. The genera are, as at present recog- 

 nized, very indefinite, and from a careful study of our species we 

 are inclined to recognize only the following: — 



Tarsi with 3d joint entire or scarcely eniarginate. 2. 



Tarsi with 3d joint emarginate or bilobed. 4. 



2. Prothorax margined at base ; 3d tarsal joint not bilobed. 3. 

 Prothorax not margined at base ; 3d tarsal joint bilobed. Prasocuris. 



3. Last joint of palpi short, truncate. Doryphora. 

 Last joint of x^alpi dilated. Chrysomela. 



4. Third tarsal joint emarginate, sides of prothorax not thickfucd, tihije 



not grooved externally, except at the tip. Plagiodera. 



Third tarsal joint emarginate, sides of prothorax not thickeni'd, tibi;e 



grooved externally. Gastroidea. 



Third tarsal joint deeply bilobed, sides of prothorax usually thickened, 



tibiae grooved externally. Lina. 



