296 INSECTA MADERENSIA. 



middle of the disk) seven or eight more (somewhat smaller than the front pair) arranged {vide 

 PI. V. fig. 9 a) as follows, — two, placed near together, at a little distance behind (but rather 

 further apart than) the front ones ; and, at about an equal distance behind these, a circlet of five 

 or six, extending to about the centre of the disk. Elytra slightly rugulose, and with both the 

 punctures and set<e (the former of which are exceedingly obscure) arranged in rows, — there being 

 a double series (one large and the other small) of each (a structure however which is not veiy 

 perceptible without the aid of a powerful glass) ; rounded and entire at their extremity. An- 

 tennm and legs testaceous. 



There are few insects which have given me more trouble in the determination of 

 them than the present one ; for, unfortunately, the unique example which I possess 

 (extracted from out of a cobweb, in a dead state, beneath the bark of a Spanish 

 chestnut-tree at Santa Anna) is too much mutilated to afford a full view of all its 

 parts. Hence it is not surprising that, before I had accurately examined such of 

 its members as were decipherable, its enormously developed mandibles (at least 

 for these groups) shoidd have led me to imagine that it embodied the t^-jie of a 

 well-marked and very anomalous genus. Fiu'thcr investigation however has 

 satisfied me that it is a true Leijiurthrum, — its l-jointed tarsi (which I have been 

 able most clearly to recognise) and peculiar tibise at once associating it with the 

 other three representatives described Ijelow. The existence moreover of the usual 

 pair of tubercles witliin the front margin of its pronotum, and of the smaller ones 

 behind tliem (the arrangement of which is, in this instance, exceedingly beautiful), 

 in connection with a similar sculpture to that which obtains in the remaining 

 forms, will still further tend to remove all doubt as to its correct generic identifi- 

 cation. Its ample mandibles therefore (which, after aU, perhaps, may be less 

 prominent in reality than they seem to be, — since the single damaged individual 

 which I captui'ed might have been accidentally so distorted as to cause the head 

 to be pvished forward somewhat unnaturally, but which in all probability would 

 not be perceived to be unnatural in an object thus small) can be only regarded as 

 of specific importance, — a i-emark which ■ndll equally apply to the distribution of 

 the raised points with which the anterior disk of its prothorax is furnished. As 

 regards the species however, it is imquestionably most distinct and interesting, — 

 reeeduig from all the rest, not only in this singularity of its mandibles (which 

 cannot possibly be entirely the result of chance, if indeed, as I am by no means 

 convinced, it be so at all), but likewise in its much greater bulk, paler hue, and in 

 the collocation of its prothoracic pustules. These last in fact {vide PL V. fig. 9 a) 

 should be especially observed, since they do not appear to be dispersed ii-regularly 

 about (as, when they exist at all, is usual in these groups, and which is partially 

 the case with its other Madciran allies), — but in a given order, wliieh will be best 

 understood by a reference to the figm'c, and which shoidd be avcU noticed, since it 

 is the modification which it is the tendency of the other species to assume also, 

 even though the symmetry be less perfect in them than it is T\-ith the L. mandi- 

 bnlnre. Of these tubercles the foremost two are slightly the largest ; whilst the 



