1879. J PHYTOPHAGOUS COLEOPTERA. 789 



black, shining. Scutellum black, trigonate. Elytra dilated poste- 

 riorly, with a shallow depression below the basilar space, and several 

 others near the lateral margins ; another longitudinal sulcation runs 

 parallel with the latter, but finishes at some distance before the 

 apex ; surface minutely and closely punctate, dark violaceous blue. 

 Underside and legs black ; abdomen flavons. 



I unfortunately possess only one specimen, and that a female, of 

 this distinctly-coloured species ; the antennae in the male will pro- 

 bably show the same dilatation as in the other species belonging to 

 this genus. 



Genus Nestinus, Clark. 



31. Nestinus flavo-marginatus, sp. nov. 



Elongate, parallel, rugose-punctate; finely pubescent. Flavous ; 

 base of the head, three transversely-placed spots on the thorax, an- 

 tennae, tibiae, and tarsi black ; elytra metallic cupreous, the margin 

 flavous. 



Length 5-5| lines. 



Bab. Mexico. 



Head rugose-punctate, with a fine longitudinal median groove at 

 the vertex extending to the clypeus, flavous, with an elongate black 

 spot from the middle of the base to almost the anterior margin of 

 the eyes ; apex of labium and the palpi black ; antennae about half 

 the length of the body, black, basal joint thickened, robust, second 

 short, third of double the length, fourth joint longer than the third 

 and the longest. Thorax transverse, sides nearly parallel, all the 

 angles slightly thickened, the posterior ones oblique ; surface ob- 

 liquely depressed at each side, longitudinally grooved in the middle, 

 irregularly rugose-punctate, flavous, a spot at each side near the 

 lateral margin, and another in the middle, a little distance from the 

 base, black. Scutellum black, finely punctate and pubescent. Elytra 

 closely rugose-punctate, finely flavous-pubescent near the margin, 

 metallic cupreous, the lateral margins and apex flavous. Tibiae and 

 tarsi black. Claws bifid. 



The flavous margination of the elytra will distinguish this species 

 from those described by Clark. 



Genus Diabrotica. 



32. Diabrotica marginella, sp. nov. 



Subelongate, widened behind. Flavous; antennas (joints seventh 

 and eighth excepted), base of head, and two spots on the thorax 

 greenish black. Elytra strongly punctate, broadly margined, me- 

 tallic green, lateral and sutural margins, as well as the apex, 

 flavous. Upper surface of femora and the tibiae and tarsi black. 



Length 3-4 i lines. 



Bab. Costa Rica. 



Head longer than broad, swollen, impunctate, front impressed with 

 a small fovea ; encarpae obsolete ; carina not visible ; lower part of 

 face flavous, labrum and vertex blackish green ; antennae two thirds 

 the length of the body, filiform, the second joint short, the rest of 



