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Show 418 INSIWT .\. o~• six strong teeth. The mentum is proportionally sh orter and wider than that of the same Coleoptera, and less narro we d super1. orl.y . The me. sosternum is frequently prolonged into a h orn or bl unt· pomt, extendmg between the second legs and even be d 1 , . .yon them he scutellum IS usually large. The tarsial hooks are ' 1 unequa. 'v'uv 'I t h t 11 e except1. 0n o f a small number, these Xge nerally 1 .. 1 . 1 · 1 · Y ophth are pecu 1ar •t o t 1e equator1a .c ountnes of the weste1·n c on t'J nent, . Here, as . In all t. he precedmg Scarab;Eides ' we find no axt'I I ary p1ece( 1) filling the mterval comprised between the poste r1· 0r angles of the thorax and the exterior angles of the base of the 1 t W 'I fi . e y ra. e w1 1 r·st speak .of those subgene1·a in which the middle of the pectus presents no pomt or horn. HExonoN, Oliv. Fab. The bo. dy i.s almost orbicular and plane beneath'· the head square an. d received mto a deep emargination of the thorav,.,•., the out er mar· gm of the elytra dilated and preceded by a small groove; the legs are slender, and the hooks of the tarsi very small and eo•u a1. T?e labrum is not apparent. The antenna} club is small. The max11lre are strongly dentated(2). CYoLOOEPHALA, Lat.-Chalepus, Mac L.-Melolontha, Fab. The b~dy o.void; head free; elytra slightly bordered, without any lateral ?llatatJon or groove; terminal joint of the anterior tarsi cia· vate, with unequal hooks, both bifid. The anterior margin of the labrum is apparent. The mandibles are narrow, without any notable emargination or sinus on the outer side, and project but slightly outwards(3). In the :ollowing. subgenera, the sternum projects between the second pa1r of legs m a conical point, more or less long, pointed or rounded at the extremity. ( 1) A lateral portion of the sternum larger and thicker than usual, and which perhaps corres.p?nds to that small rounded scale (the tegula of some authors) found at the origm of the superior wings of Hymenoptera. See the Mem. sur le thorax des Insectes, by M. Audouin. (2) See Oliv., and Lat., Gener. Crust., 11, p. 106. (3) The Melolonthre gcminata, barbata, castanea signata ferruginea melanlltt' phala, pallens, &c., of Fabricius.' In the first, the ~andibl:s are strong: arcuated, and. hooked at the end. Those of theM. signata, melanocephala, &c., are smaller, straight, truncated, or obtuse at the end. The summit of the maxilla: and mentum is also furnished with hairs. From such characters we might form a separate su!J. genus of these and analogous species. They all belong to South America. COLEOPTERA. 419 The anterior margin of the labrum is always apparent. The mandibles are generally crenulated or dentated on the outer side. The tarsial crotchets are unequal. In the CHRYSOPHORA, Dej. The posterior legs of the males are very large, the thighs very thick, the tibire arcuated and terminated at the inner angle in a stout point( I). RuTELA, Lat.-Rutela, Pelidnota, Mac L. Kirb.-Oplognathua, Kirb. Mac L. No remarkable difference in the proportions of the legs in the two sexes; the mentum almost isometrical; the scutellum small or moderate; sternal point short and not reaching to the origin of the two anteriorfeet. The body is ovoid or oval(2). The MAoRASPis, Mac L.-Cetonia, Fab. Differs from Rutela in the proportions of the mentum which is evi- · dently longer than it is broad; in the short and rounded form of the body; in the length of the scutellum, which is at least one-third of that of the elytra, and of that of the sternal point, the extremity of which reaches to the origin of the two anterior legs or extends beyond it. The mandibles are almost triangular, and their extremity is pointed &nd emarginate. The maxillre are furnished with several teeth. The mentum forms an elongated square slightly narrowed near the superior extremity; its superior margin is destitute of cilia. One of the crotchets of the tarsi, at least of the four anterior ones, is bifid, the other en tire( 3;. CHASMODIA, Mac Leay. The Chasmodire are similar to the Mac rasp ides in the general form of their body, the proportions of the scutellum and of the sternal point; but the extremity of the narrower mandibles is obtuse and entire; the maxillre have only two teeth and a pencil of hairs, and the mentum is an elongated ovoid narrowed near the superior ex- (1) Melolontha chrysochlora, Lat.; Voy. de MM. Humb. and Bonpl., II, xv, 1, fern.; 2, male;-Scarabmus macropus, Shaw, Nat. Miscel., CCCLXXX, iv. • (2) See Catal. de la Coll., &c., Dej.; Horre Entom., I, Mnc L. and Encyc. Method., article Rutele. The chat·acters of the genera Pelidnota and Oplognathm do not seem to me sufficiently determined. (3) See Catal., &c., Dej.; Borre Entom., 1; Ency. Method., art. Ruttle. |