506 COLEOPTEKA OF NORTH AMERICA. 



Tribe I.— RHY]VCHOPH©I5IIVI. 



The species of this tribe are of large size, and with tlie excep- 

 tion of Rhynchophorus, have tlie mandibles turned outwards as 

 in the llhininsD; in the genus just mentioned, the mandibles are 

 of the usual i)incer-form with three small apical teeth. The 

 funicle of the antennre consists of six perfoliate joints, strongly 

 constricted at the outer end; the club is transverse, trapezoidal, 

 corneous, Avith the terminal face fiat, spongy, and sensitive. 



One species, R. crucntatu^, represents this tribe in the 

 Southern States. It is parasitic on Chamserops palmetto. In 

 consequence of the extension of the mcsothoracic epimcra up- 

 Avards, the humeral portion of the elytra is truncated, as in 

 Barini. The tliird joint of the tarsi is but little wider than the 

 second, not emarginate, fringed at the apical margin beneath. 

 In the % the tibiie, and to a less extent the thighs are densely 

 fringed with long yellow hair on the inner side: in the 9 the hairs 

 are much less dense. The genital segment is sometimes pro- 

 truded; it is nearly smooth, and finely channelled above in both 

 sexes, but is longer and narrower in the ?, in which sex also the 

 pvgidium is more flattened, and more obliquely narrowed at the 

 tip. Another species, R. palmarum, occurs in the southern part 

 of California: 



Tribe II.— SPHEiXOPHOR5]Vl. 



The species of this tribe are rarely large, but never very small. 

 The mandibles are always pincer-shaped, with three apical teeth. 

 Tlie metothoracic epimera are large, and truncate at the outer 

 side, so that the outline of the elytra near the base is straight, 

 and not oblique as in the preceding tribe ; the metathoracic epi- 

 sterna are rather narrow, and the epimera small, though quite 

 obvious. 



The following genera have been observed in our fauna : — ■ 

 Spongy portion of antennal club flat. Scyphophorus. 



Spongy portion of antennal club convex. -. 



2. Anterior coxffi widely distant. Metamasius. 

 Anterior coxse narrowly separated. o. 



3. Third joint of tarsi patellate, spongy surface not divid(Hl. 



Cactophagus. 

 Third joint of tarsi patellate, spongy, narrowly divide^l. 



Rhodobcenus. 

 Third joint of tarsi pilose at the sides or glabrous ; , 4. 



