442 PROCEEDINGS OF THE NATIONAL MUSEUM vol. m 



cally. Prosternal process narrow, convex between coxae, its apex 

 acute and secondarily reflected; epipleura entu'e, very narrow at apex; 

 tibiae all slender, tarsi relatively long, hindtarsus with basal segment 

 the longest but only slightly longer than fourth. 



The above description has been purposely kept brief since only one 

 species of the genus (fortunately the type species) has been studied, 

 rendering it difficult to estabhsh generic limits with any certainty. 

 This species resembles a small Platydema in general appearance, but 

 may be distinguished from members of the latter genus by the distinct 

 vestiture of fine recumbent setae clothing the entire dorsal surfaces. 

 The antennae are longer and more slender than is true of most species 

 of Platydema, and the terminal segment of the maxillary palpus is 

 elongate. Both of these characters, however, fall well within the 

 range of variation observed among species of Platydema. 



Gebien (1940) lists eight species of Alphitophagus in the world fauna. 

 No less than six of these have the same general color pattern, and it 

 would not be surprising to discover some synonymy involved among 

 these names. It is possible that the system of coloration should be 

 listed among the generic characters, but this has resulted in con- 

 fusion in the past. Marseul (1876) described four species which he 

 placed in Alphitophagus, partly, at least, because of the color pattern. 

 Three of these have been transferred to Platydema by subsequent 

 workers and the fourth is retained somewhat doubtfully in Alphi- 

 tophagus (Gebien, 1940). 



The peculiar development of the male clypeus described below 

 perhaps deserves consideration as a generic character, but its status 

 is unkno\vn in other members of the genus. As far as can be deter- 

 mined, it has no counterpart in Platydema or related genera. Until 

 further information is available, it seems advisable to reserve judg- 

 ment on this character. Thus it can be seen that in the final analysis, 

 the genus Alphitophagus is retained as distinct from Platydema on 

 the basis of but one rather poor criterion — the dorsal vestiture. 

 There are too many gaps in our knowledge of either of these genera 

 on a worldwide basis to justify lumping them together, so the present 

 distinction is herein retained. Considering only the Nearctic and 

 Palaearctic fauna, this appears to be quite valid, and will suffice for 

 the present treatment. 



Alphitophagus bifasciatus (Say) 



Plate 6 (Figs. 55, 56, 57) 



Diaperis bifasciata Say, 1824, p. 268. 



Alphitophagus quadripustulaius Stephens, 1832, p. 12, pi. 24, fig. 1. — Redten- 

 bacher, 1858, p. 603; 1874, p. 107.— Jacquelin du Val, 1861, p. 299, tab. 73, 

 fig, 363.— Thomson, 1864, p. 255.— Seidlitz, 1875, p. 362; 1891, p. 517, p. 554; 



