TETRAMEROUS PLANT-BEETLES. 



1T3 



[Fig. 86.] 



|f Haltica (Graptodeea) chalybea, niiger:— The Grape- 



three black dots arranged in a 

 triangle; length a quarter of an 

 inch ; this is the I), triangularis, 

 Say. Another species liable to 

 be confounded with this is the 

 D. collaris, Fab., but in this the 

 thorax is yellow without spots, 

 and the under side of the ab- 

 domen is dull yellow. Orches- 

 tris, Kirby, is the genus which 

 contains the common cabbage 

 and turnip flea-beetle, and its 

 allies. They are about one -tenth 

 of an inch long, black, with a 

 broad waving yellow stripe 

 along the middle of each wing- 

 cover. Species closely resem- 

 are equally 



[Fig. 87.] 



Tine flea-beetle ; a, grape leaf eaten by young larvas ; b, Dling eaCD. Otncr 



larva, magnified; c, earthen cell, in Which the insect i j „j. ^,^A /lr><:.f».ni-.fi-r-r» iv. 



transforms ; d, beetle-after Eiley. abuudaut and dCStrUCtlVe lU 



Europe and in this country. The generic name means a dancer or 

 jumper. Lomjitarstts, Latr., contains many small and closely allied spe- 

 cies of a brownish color, and distinguished as the name implies^by the 

 greatly elongated first joint of the hind tarsi. Systena, Chev., 

 is most readily distinguished by the elongate, narrow form of 

 the species. The Systena blanda, Melsh., an eighth of an inch 

 long, pale yellow with three darker stripes, has been found to 

 be destructive to young corn, in the Middle States. The other 

 genera in the table are composed of very small species, distin- halticacha- 

 guished from the foregoing by having the elytra punctured showing the 

 in rows. Diiolia, Chev., contains but one known species, theri^? thi|hl.^ 

 I), aerea, Melsh., or brassy Dibolia, a tenth of an inch or a little more in 

 length and of a brassy black color ; found in the Middle and Southern 

 States. The species of Chwtocnema, Stephens, are found mostly in the 

 Southern States and Texas. Grepidodera, Chev., contains many very 

 small, usually black or reddish species; but one of the most common, 

 the C. Jielxines, Linn., is sometimes purple and at others brassy green. 

 This little species is said to be common to Europe and this country. The 

 little Cucumber flea-beetle, Haltica cucumeris, of Harris, has been placed, 

 in company with a few others, in a separate sub-genus Epitrix, Foudr., 

 on account of their pubescent surface. But few species of the little 

 genus PsylUodeSj Latr., have been observed. Dr. Fitch refers toone of 

 them, the P. punctulata, Melsh., as being somewhat injurious to the 

 leaves of several kinds of garden vegetables. The generic name is de- 



