of the South&im portions of South America. 47 



nalibus, et costa central! in medio interrupta, angulis lateralibus 

 acutis et retrorsum spectantibus ; elytris cum costis duabus irre- 

 gularibus a basi ad partem apicalem tertiam longitudinaliter ductis, 

 costis duabus brevioribus basalibus, et cum lineis parvis punctisque 

 elevatis crebre dispositis : elytrorum carina laterali et apice non- 

 nunquam piceo-rubris, vel piceis. — Long. corp. lO^lin. ; lat. 5 J 

 lin. 



Black or pitchy black, and glossy ; legs and antennse pitchy : 

 head rather coarsely punctured and somewhat rugose in parts, 

 and with a transverse impression : thorax broader than long ; the 

 anterior angles produced ; the sides much dilated, but at a short 

 distance from the hinder margin, with a deep notch suddenly re- 

 ducing the width of the hinder part of the thorax nearly to that 

 of the fore part, and leaving to project in the form of an acute 

 angle (the point of which is directed backwards) the dilated la- 

 teral margin ; in this notch is a small triangular projection, which 

 may perhaps be regarded as the posterior angle of the thorax, if 

 we imagine that angle to be curved forwards and slightly upwards ; 

 the dorsal surface of the thorax is slightly convex, and has some 

 scattered punctures ; in the middle, behind, is a short and small 

 longitudinally elevated ridge, and on the disc are two other ridges 

 separated by a narrowish interspace which presents numerous 

 small rugse ; on the fore-part of the thorax (which is emarginated) 

 there is a fourth little keel. The elytra incline to an ovate form, 

 and are considerably arched in the longitudinal direction ; in the 

 transverse direction the outline is but little arched : the lateral keel 

 is notched in parts, and extends nearly to the apex of the elytra, 

 sending out a small sub-apical brush : the surface is glossy and 

 uneven, and at about one-third of the distance from the lateral 

 keel to the suture is a longitudinal ridge which extends the base 

 of the elytron, but is obliterated on the apical third ; within this 

 ridge are some irregular large shallow depressions and indistinct 

 ridges ; these depressions and minute ridges are confined to a space 

 which would be included between the longitudinal rib and a se- 

 cond rib ; but that second rib is obliterated, if we except a small 

 portion at the base of the elytron, and a short minute keel in a 

 line with the point of termination of the outer and more developed 

 rib : the lateral margins of the elytra and the lateral keel are 

 pitchy red : the red colour of the lateral keel is continued to the 

 apical portion of the elytron, where it forms a broad and conspi- 

 cuous mark. 



This description is drawn up fi-om a specimen brought from 

 Mendoza by Mr. Darwin. 



Besides the species of Nyctelidce here noticed, the Marquis de 

 Breme's collection contains a true Nyctelia (Solier) closely allied 

 to the Nyct. Westwoodii of my paper : I propose to name it 



