Sound-'production in the Lamellicorn Beetles. 739 



jE. guianense of Westwood has been re-described under 

 the name of yE. SteinlieUi by Harold, the original of 

 Westwood's descri2:)tion (I have been able to compare 

 the types of both authors) being a female. This form 

 however does not properly belong to the genus, and I have 

 therefore formed for it a new genus which I shall name 



JEgidinus, gen. nov. 



Corpus breve, hand depressum : clypeus antice productus : mandi- 

 bula3 apice fissa?, extiis lobo prominente munitse : coxa^. posticaj 

 deplanata?, area stridulatoria ti'aiisversa prope marginem lateralem 

 pra)dit;ie. 



(^ clypeus apice cornu erecto armatus : prothorax antice late 

 excavatus, dente obtuso ante marginem anteriorem. 



Alia quoad in gen. j^gidinm. 



The stridulating apparatus and other features are as in 

 j^gidium, the differential characters being the differently 

 sliaped head, the lobed mandibles and, in the male, the 

 horn into which the clypeus is produced and the excava- 

 tion of the thorax, which is confined to its anterior part. 

 The genus bridges to some extent the interval between 

 jEgidium and the Old World genus Orphnus. Orphnns 

 Stroheli of Steinheil may perhaps belong to it. There is 

 another form, closely related to ^. guianensis, which was 

 found by Bates in the Amazonian region and believed by 

 him to be Westwood's species. I shall name this 



JEgidinus hrasilicnsis, sp, n. 



Convexus, niger, nitidus, corpore subtv;s, antennis, palpis pedi- 

 busque rufis ; cfipite fere la3ve, antice acuminato, paulo concavo ; 

 prothorace polite, pnnctis nonnullis lateraliter sparsutis, marginibus 

 lateralibus valde curvatis, angiilis anticis paulo acutis, posticis 

 obsoletis ; scutello parvo, impunctato, quam latitudinem longiore ; 

 elytris brevibus, lateribus ab luaueris ad apices regulariter curvatis, 

 stria si;turali lineisque punctoram vagis ; marginibus omnibus cor- 

 poreque subtus longe fulvo-setosis, metasterni medio la3ve ; coxis 

 Isete rufis, fere impunctatis ; mandibularum lobo externo longo. 



Long. 8'5 —11 mm. 



Hob. Brazil, Ega. 



This has the same general form and appearance as ^. 

 guiancnsis, but is rather smaller and is easily distinguish- 

 able by its much greater smoothness. The head is 



