﻿of Lucanoid Coleoplera. 11 



RHiETUS Westwoodii $ , Parry (var. max., ? ignota). (PI. IX. 



figs. 1 & 8.) 

 Hexarthrius (2) JVestrvoodii, Parry, Proc. Ent. Soc. 18G2, p. 108. 

 R. nigerrimus, nitidus, sublente tenuissime granulosus; mandi- 

 bulls elongatis, falcatis, apicem versus parumdeflexis, singula- 

 riter ad basin excavatis et supra infraque dente magno armatis, 

 ante medium dente acuto instructis, apicibus furcatis; capite 

 brevissimo, prothorace angustiori, clypeo transverse baud pro- 

 minulo, concavo, antice in medio angulato ; prothorace trans- 

 verso, lateribus sinuatis dente parvo acuto armatis ; elytris 

 elongatis, subparallelis ; tibiis anticis 4 aut 5-spinosis, inter- 

 mediis extus in medio dente acuto armatis, posticis simplicibus. 

 Long. Corp. unc. 2, lin. 3 ; mandib. unc. 1, lin. 3. 

 Hab. Ind. Or., aut Arcbip. Ind.(?) 



I am indebted to J. C. Bowring, Esq., for tbe possession of this 

 magnificent and unique species. It is one of the largest of the 

 Lucanoid Coleoptera, measuring Sg inches. 



Hexarthrius Detrollei S j Parry (var. max., ? ignota). 

 (PI. IV. fig. 1.) 



H. niger ; mandibulis exsertis, supra et intus denticulatis, ad 

 basin singulariter excavatis ; capite supra bituberculato ; 

 elytris plaga posticd castanea. 



Long. corp. fere unc. 2 ; mandib. lin. 9. 



Hab. Siam. Specimen unicum in Coll. Mniszech. 



Closely allied to H, Parryi, Hope, but of a more elongate and 

 slender form. Mandibles straighter, with the interior portion of 

 their base deeply excavated. The binodose elevations on the 

 head of H. Parryi are replaced by tvi^o elevated conical tubercles. 

 The prothorax is narrower and longer, with the anterior tuber- 

 cular angle more prominent. The apical yellow plaga of the 

 elytra does not extend so far towards the base ; and the punctua- 

 tion of the mandibles, head and prothorax is infinitely stronger ; 

 the legs are more slender. 



I am indebted to M. Henri Deyrolle for the characters of this 

 species, at present unique in the museum of Count Mniszech, and 

 received from Count de Castelnau. 



Hexarthrius Chaudoirii, H. Deyrolle, MS. 

 This new species from Sumatra, allied to H. Rhinoceros, is in 

 the collection of Count Mniszech. M. Henri Deyrolle proposes 

 to describe it in the Ann. Soc. Ent. Fr. for 1864. 



