COLEOPTERA 457 



CvRTOSTOLUS, gen. nov. 



Sulci antennarii sat convergentes, prosternum processu post coxas parum curvato, 

 coxae posteriores distantes. Alae abbreviatae. 



Plate XIII. hg. 24 «, wing. 



This genus is separated from Ortliostolus on account of the aborted wings. This 

 character seems to be quite constant. The species has quite the appearance of the 

 species of Ortliostolus allied to O. sordidus, and the only other structural distinction I can 

 observe is that the prosternal process is slightly more curvate. 



It should be noted that the wings of this species are not so reduced as they are in 

 the genera Nesapterus and Apetimis : the size of the wings is ne\'ertheless very little 

 variable ; if we suppose that the species is on the way to becoming nearer to the apterous 

 condition it is most difficult to believe that natural selection would aid this in any direct 

 way. In other words the variation in the size of the wings is not of selectional value. 

 D. S. 



( I ) Cyrtostohts siibalatus, sp. nov. 



Latus, depressus, rufo-fuscus plus minusve infuscatus, marginibus rufescentibus, 

 leviter nitens, crebre punctatus, subtile pubescens ; antennis pedibusque rufo-fuscis ; 

 prothorace transverso, disco quadri-impresso, angulis anterioribus rotundis, posterioribus 

 plus minusve argutis ; elytris obsolete impressis et sulcatis, marginibus posterioribus 

 fortiter curvatis ; abdomine obsolete impresso. Long. corp. 4| — 6^- mm., lat. corp. 

 2\ — 2|- mm. 



Plate XIII. fig. 24, t. 



This insect is immediately distinguished from O. sordidus by its reduced wings. 

 The prothorax is longer than in O. sordidus. It agrees with the latter in having the 

 male supplementary segment strongly acuminate. % pygidium somewhat narrow, 

 rounded in outline at the extremity ; J pygidium more truncate, with a very slight 

 notch at the apex. The species is variable in size ; some smaller specimens are lighter 

 and more uniformly red-brown. 31 specimens. 



We have examined several specimens with regard to the condition of the wings ; 

 though the species is a variable one, in this respect it seems to be constant. The 

 wings are not completely aborted, but a little shorter than the elytra and broad at the 

 extremity, so as to be roughly triangular (see PI. XIII. fig. 24 a). 



Hab. Maui, Haleakala 4500 — 5000 ft., in. and iv. 1894, v. 1896 (nos. 350, 

 600, &c., Perkins). H. S. 



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