292 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



boge-yellow. Joints 2-12 each with a dorsal transverse corneous plate of a somewtat 

 deeper brownish -yellow ; a medial impressed line on all the joints, and two distinct 

 impressions each side of it on all the plates; a lateral substigmatal series of ovoid 

 tubercular plates, and 7 ventral ones, on each abdominal joint, arranged as in Fig 25, rf, 

 varying in size so as either to be well separated or contiguous, those on joints 11 and 

 12 coalescing. Head flattened, depressed ; mandibles moderately stout, with a small 

 middle tooth; antennae not reaching beyond mandibles, 4-jointed, the 3d bent inward, 

 the 4th outward ; maxilla with 2d joint slightly shorter than the basal, with tapering 4- 

 jointed outer and 2-jointed inner x>alpi ; mentum short ; labium faintly bilobed, the 

 terminal joint black ;.the palpi 2-jointed, the terminal joint small and bent inward ; 

 inside of 2d maxillary joint and tip of labium armed with setse. Pmthoracic joint 

 rounded, faintly striate at front and hind borders ; legs pale, with an X-shaped black 

 mark at outside of coxce, which are stout ; trochanter very short from above ; tarsus 

 distinctly 2-clawed, and nearly as long as tibia ; stigmata pale, lateral, the lirst pair ou 

 a fold on the front edge of the mesothorax ; anal proleg horizontal, rather obiiquely 

 truncate beneath, not much longer than joint 12, the cerci not reaching beyond it, and 

 faintly triarticulate, with the tip black. Average length, 14™™. 



Pupa. — Unarmed, long, with the tips of tarsi broadly and distinctly bifid. 



Described from many locust-egg-feeding specimens. 



Other Carabid larvse no doubt prey upon these eggs, since we have 



a 



Fig. 27. — Penxsylvania 

 Ground-beetle.— a,aiiterior tarsus 

 anrl notched tibia; &, beetle. (After 

 Eiley.) 



Fig. 26.— Harpalus ? Larva.— 5, under side of head ; h, i, 

 j, under side of different joints of body. (After Eiley.) 



discovered two species, distinct from either of 

 the above, feeding on the eggs of other 

 locusts. We introduce the figure of a larger 

 species (Fig. 26), and its probable parent, the 

 Pennsylvania Ground-beetle {Harpalus pennsylvanicus DeGeer, Fig. 27). 

 Blister-beetle larvee — Of all the different insects that feed on 

 the eggs of our locust, these, though not the most common or effective 

 in checking locust increase, are nevertheless the most interesting; first, 

 because of the singular changes which they go through; secondly, 

 because their larval habits remained so long unknown, notwithstanding 

 the frequency with which the beetles themselves recur in great numbers 

 on different plants. The habit of feeding on locust eggs in the larva 

 state, though suspected by Mr. Eiley in 1876, was'first demonstrated by 

 him in 1877. These blister-beetles are all elongate in form, and possess 

 the property, in common with the Spanish-fly of the shops, of drawing 

 blisters on the human flesh. Many of the species show great partiality 

 to the Potato, and were for a long time considered the most formidable 

 enemies of this esculent. The Striped blister-beetle (Fig. 30 ; PI. lY, Fig. 

 10) is familiar to most farmers, in the more Southern States especially, 

 and swarms at times on potato and tomato vines. The Ash-gray blister- 

 beetle (Fig. 31, a) ranges farther north, and attacks (besides the Potato) 

 the Honey-locust, various kinds of beans, lucerne, apple-trees, beets, &c. 

 The Margined blister-beetle (PI. IV, Fig. 11), aside from attacking 

 potato and tomato vines, is often injurious to the egg plant, the Ken- 

 tucky coffee- tree {Gymnocladus canadensis), spinach, and other garden 



t 



