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sent for examination ; specimens were in the Macleay Museum 

 from the Darling River. The species in general appearance- 

 is fairly close to cordipennis, but the space between the 

 scrobes is strongly narrowed posteriorly, whereas on that 

 species it is slightly dilated posteriorly; the clothing also is- 

 different. As in some respects it seemed to agree with the 

 description of umbratus, some years ago specimens were sent 

 for comparison with the type of that species, and of these the 

 late Rev. T. Blackburn wrote, "Specimens sent are certainly 

 not umbratus. Apart from colouring (which is very different) 

 it differs, inter alia, as follows : Shape of prothorax — in 

 umbratus, less rounded laterally with greatest width in front 

 of middle; in your species well rounded, widest at 

 middle. Interval between scrobes in umbratus continuously 

 and evenly narrowing from base to apex, in your species at 

 its narrowest near base." The latter character will also dis- 

 tinguish the species from medio fusca, which in many respects 

 it resembles. There is a whitish ring on each of the femora. 



Essolithna nigescens, Pasc. (formerly Chaodins). 



A cotype of this species sent for examination has the 

 front coxae exactly as on Essolithna rattida, that is to say, 

 the intercoxal process is rather narrow, about half the width 

 of that between the middle coxae and transversely cleft at its 

 narrowest part; the claws are unidentate. It was only on 

 these characters (in comparison with Poly parades) that 

 Chaodius was proposed as new, and I regard it is absolutely 

 synonymous with Essolithna. The elytra were described as 

 subparallel, but the shoulders are rather strongly rounded, 

 the sides at the apical fourth are coarctate, and the sides 

 between are gently rounded; possibly the sides are sexually 

 variable, but the word subparallel as applied to the cotype 

 would be misleading. The species is extremely close to 

 cordipennis, but differs in having longer and narrower 

 elytra. 



Essolithna umbrata, Blackb. (Pephricus). 



On closely examining a cotype of this species each claw 

 is seen to have a smaller one soldered to it at the base; 

 the smaller claw is invisible from most directions, but its. 

 presence on this species and its gradual enlargement on 

 several species of Polyphrades, till at the apex the claws are 

 noticeably cleft, but of equal size, seem to imply a doubt 

 as to whether Essolithna (to which genus Pephricus has 

 already been referred) can be eventually maintained aa 

 distinct. 



