140 Zoological Society, 



straight, but the anterior angles are produced and the posterior an- 

 gles are slightly produced. The width of the fore and hind parts 

 of the thorax is nearly equal, it being but slightly narrower in front, 

 and the sides deviate but little from a straight line ; a faint dorsal 

 channel is observable, and a groove runs parallel with and close to 

 the lateral and anterior margins. With the assistance of a strong 

 lens, minute punctures may be observed scattered over the upper 

 surface of the thorax, and some minute tubercles on the under. 

 The elytra are convex, and of a short rounded form, the width and 

 length being very nearly equal, if we do not include the produced 

 apical portion, which is more dilated than in most of the genus, and 

 is nearly flat. A groove runs close to and parallel with the lateral 

 keel, both above and below, and this keel is distinctly crenulated. 

 The upper surface of the elytra presents numerous indistinct and very 

 shallow fovea? . The abdominal segments are almost smooth. The 

 legs are proportionately rather longer than in N. Icevis. 



Mr. Darwin found this species at St. Cruz in the month of April. 



Nyctelia Newportii. Nyct. elongato-ovata, nigra, nitida ; capite 

 transverse impresso ; thorace lato plus quam longo, lateribus rotun- 

 datis; antice etpostice latitudine compari; superne mininie convewo, 

 impunctato, ad latera rugis parvulis obliquis ; elytris ovatis, Icevi* 

 bus, plagd suturali valde impressis, marginibus lateralibus crenu- 

 latis. 

 Hab. Patagonia. 

 Long. corp. 10 lin. ; lat. 6 lin. 



This species is rather smaller than N. Icevis, and differs moreover 

 in being of a more elongated form, and most especially in the form 

 of the thorax, which is narrower and nearly equal in width, in front 

 and behind : the apical portion of the elytra is much less produced, 

 and the produced portion is broader. The head is sparingly punc- 

 tured at the sides, and has a curved impression, the chord of which 

 is rather in front of the insertion of the antennae. The thorax nearly 

 one-third broader than long (taking the length from the anterior 

 and posterior angles) ; it is broadest in the middle, and a trifle nar- 

 rower in front than behind ; the lateral margins form an even curve ; 

 the anterior part is emarginated, the emarginated portion being in 

 the form of a segment of a circle, and a little less than a semicircle : 

 the anterior angles acute, and the posterior angles form very nearly 

 right angles : the hinder margin of the thorax is nearly straight, but 

 the line descends slightly towards the angles. The surface of the 

 thorax is very little convex, and almost impunctate, there being but 

 a few scattered very minute punctures ; on the sides, running inwards 

 and upwards, are a series of minute grooves, like scratches, and on 

 the hinder margin a faint trace of very short longitudinal grooves 

 is visible. The elytra are ovate, convex, smooth, and glossy ; the 

 region of the suture is broadly and rather deeply depressed ; the 

 lateral keel is prominent and distinctly crenulated, and joining this 

 keel are a series of shortish transverse furrows. The under sur- 

 face of the body and thoracic segments is remarkable for the almost 



