256 FAUNA HAWAIIENSIS 



Our small series of examples exhibits a moderate amount of vi^^iation as to s 

 and blackness; the abdomen is nearly always flavescent. The striatiQ,-, gf [)^^ elytra is 

 a little less deep in the small, dark individuals. 



The only distinction between Mecyclotliorax robiistiis, and Thrt.^^Qij^Qj,Qj^^ robustus, 

 beyond the generic character, is a slight difference in the form of the hinder part of the 

 thorax ; this in M. robnstiis is rather less constricted behind, and ^^g hind ano-le is 

 slightly more acute, the side margin there being less directed upwards.^ This distinction 

 is but slight, and is less than occurs as variation in some of the allies, gQ (-^^j \^ jg qujte 

 probable that the two may be dimorphic forms of one species. They Sggj^ j-q ]-,g gQ f^^ 

 as I can judge, very closely associated geographically. The locality Viumbers for this 

 species are 363, 599, 605, 621, 622, 679, 680. 



Hab. Maui. Haleakala, on several occasions, at an elevation of iqoo or 5000 ft. 

 (Perkins). 



(29) jMccyclothorax occult us, sp. nov. 



Robustus, niger, supra aeneus, parum nitidus, antennarum basi, pafpig^ pedibusque 

 rufis ; prothorace fortiter transverso, lateribus rotundatis, angulis po^tgj-JQi-ibus fej-g 

 rectis ; elytris minus profunde striatis, striis impunctatis, externis obsjQigj-ig^ Loner. 

 5^ mm. ' 



Distinguished, in this group of large forms with brassy surface and' broad base to 

 the thorax, by its very short thorax, and the slighter striation of the elytra 'p^e thorax 

 has a definite red margin, and the sides are sinuate exactly in front of the lijnd ano-les as 

 if to prevent these from being obtuse ; the anterior impression and medi.j,-, channel are 

 distinct, and the base is much sculptured. The striation of the elytra is ^-.^j^g distinct, 

 but the outer striae are obsolete, and all except the sutural one are ver^ fajnt at the 

 extreme base. One specimen. 



Hab. Molokai. 4500 ft., June i8th, 1893 (Perkins). 



(30) Mecyclotliorax aiiiaronics, sp. nov. 



Major, robustus, niger, supra aeneus, antennarum basi, palpis pedibusqi,g j-ufis illis 

 extrorsum, femorum basibus tibiisque fuscescentibus ; prothorace fortiter tra^gygj-so, ad 

 basin breviter constricto ; elytris striis omnibus integris, profundis, punctatis. L Qp,o-_ y nim. 



Plate VII. fig. 7. 



The largest insect of the Hawaiian Pterostichides, and one of the m(-,gj- distinct ' 

 species. Head very broad. Thorax strongly transverse, with strongly round gj gides a 

 short basal constriction and rectangular hind angles ; very shining, the anterior impression 

 moderately, the median channel very, distinct, the broad base much punctate ; ^^e lateral 

 margin rather strongly explanate, more or less rufescent. Elytra large, ob|Q[^„ j-^g 

 shoulders but little rounded, all the eight striae deep from base to apex an^^i rather 

 strongly punctate ; shining, brassy, the raised margin and tip rufescent. Five sp,g(,ij^gj^s_ 



