168 THE ORDER OF COLEOPTERA. 



mela caruleipennis. Say also described two other and similar species, 

 but without the yellow thorax, which he accredits to the Missouri terri- 

 tory. Flicedon, Chev., contains a few small species, the-type of which 

 is the P. viride, of Melsheimer. Prasociiri'S, Latr., contains three spe- 

 cies, none of which are common. Plagiodera, Chev., is composed of a 

 number of species of very variable color, and even the same species, as 

 in the cases of the not uncommon P. scripfa and P. interriipta, which 

 are ordinarily yellow with blackish spots, are sometimes found wholly 

 blue-black or green. This genus was formerly known as Melasoma, 

 Dillwyn ; but the name is not properly applicable to the species, and 

 besides was pre-occupied by Latreille — as we have seen in a former 

 pai't of this work — as the general name of the black-bodied heteromera. 

 It has been therefore replaced by Plagiodem, Chevrolat, meaning trans- 

 verse thorax, and applied to them because the thorax is much wider 

 than it is long. 



Chrysochus, Chev., in the group of Eumolpini, meaning literally a 

 f/oldsmith, is the generic name of the beautiful golden-green beetle, about 

 four-tenths of an inch long, found on the dogs-bane and other species of 

 Apocymim. It has usually been referred to the genus Eumolpus, but is 

 now known as the Chrysochus auratus, Fabr. It is common throughout 

 both the Eastern and Western States, and has been found as far 

 west as Arizona. Another similar species, but usually a little larger 

 and of a deep blue-green color, has been found in Oregon and Califor- 

 nia. It is the Ch. cobaltimis, of LeConte. Typophorus, Chev., contains 

 three closely allied species, the type of which is the T. tricolor, Fab., 

 found in the Middle and Southern vStates. The next five genera — Paria, 

 Colaspis, Iletachroma, Heteraspis and Xanthoma — contain a large num- 

 ber of small, brown insects, though some species of Colaspis have a 

 metallic lustre. Paria is distinguished from the others by the ear-like 

 lobes on the anterior margin of the thorax, which partly cover the eyes. 

 The same lobes exist in Chrysochus, but are situated lower down. The 

 genus Fidia, of Dejean, is composed of a somewhat larger species, of a 

 dark chestnut or blackish color, but with a mealy surface produced by 

 dense, short, prostrate hairs. The insects of this genus have an econo- 

 mic interest in consequence of damage done by them to the leaves of 

 the grape-vine. The leading type is the F. viticida, Walsh. Dr. Le- 

 Conte regards the longipes, Mels., and the viticola, Uhler, as only varie- 

 ties of this species. 



Sub-family CRTPTOOEPHALIDES. 



This group is founded upon the genus Gryptocephalus, of Geoffroy, a 

 term meaning concealed head, and given to these insects because the 

 head is so deeply immersed in the strongly convex thorax that it can 

 be scarcely or not at all seen when viewed from above. The pygidium 



