270 



A. Antennae with joints 2-4 not carinate ; elytra witli fine rows of punc- 

 tures arranged in pairs ; margin green, mexicanus. 



B. Antennae witli joints 2-4 compressed and carinate: 



A. Hind tibiae $ not densely pubescent on inner side : 



a. Labrum broadly and feebly trilobed ; elytra not sulcate, humeral carina 

 moderate, hind tarsi long and slender, depressus. 



h. Labrum distinctly trilobed ; elytra sulcate towards the sides, elytra more 

 narrowly margined : 



Less slender, elytral rows of punctures double or obsolete, duplicatus. 



More slender, elytra rows single, obsolettis. 



B. Hind tibiae $, densely pubescent on the inner side near the tip ; 



Elongate, humeral carina long, elongatus. 



Broader, humeral carina shorter : 



Humeral carina moderate, punetulatus. 



Humeral carina very short, californicus. 



5. P. mexicanus, Gray, Griffith's An. Kingd., 274, pi. XIL, f. 1 ; Laporte, 



Hist. Ins., L, 63. 

 P. viridans, Lee. Proc. Ac. Nat. Sc, Phila., 1858, 61. 



One specimen, collected by Mr. Scliott, while attached to the 

 United States and Mexican Boundary Commission, probably in 

 Arizona. The form is rather slender, the elytra less convex than 

 in elongatus, ^'lih. distinct rows of punctures arranged in pairs; 

 the humeral carina is very short; the lower joints of the antennae 

 are not at all compressed or carinate ; the labrum is broadly tri- 

 lobed, the middle lobe wider than the side lobes, though distinctly 

 separated from them ; the mandibles are rather deeply rugose ; the 

 side margin of the prothorax is narrower than in the other species 

 of the group, and with the base and the sides of the elytra, is tinged 

 with metallic green. 



6. P. depressus, Bonelli, Obs. Ent. 2d, 45 ; Say, Trans. Am. Phil. Soc, IL, 19 ; 



Ed. Lee. n., 145 ; St. Farg. et Serv., Enc. M6th., 

 X., 15 ; Dej. Sp. Gen., L, 406 ; Aud. and Brulle, . . . 

 61 ; Laporte, Hist. Ins., I., 63 ; Lee. Ann. Lye, IV., 

 145, pi. VII., f. 1 ; Putzys, Prem. Ent., 6. 



Scarites depressus, Fabr., Ent. Syst., I., 94 ; Syst. El., I., 123 ; Oliv., 

 No. 36, 5, pi. IL, f. 15 ; Herbst, Kiifer, X., 254, pi. 

 CLXXV., f. 4 ; Latr., Hist. Crust., et Ins., VII., 

 376; Beau vols, Ins. Af r. and Amcr.,106, pi. XV., f .3. 



Scarites complanatus, Gmelin, Linn. IV., 1993. 



var. P. morio, Lee. Ann. Lye, IV., 145, pi. VII., f. 2. 



var. P. laevis, Lee, ibid.. 146, pi. VII., f. 4. 



