I 



Mr. T, V. Wollaston on Additions to Madeiran Coleoptera, 339 



porrected and acute, very finely margined both laterally and 

 behind, and more or less scooped-out (sometimes very deeply so) 

 on either side towards the basal angles, which are consequently 

 more or less prominent or acute. Elytra almost parallel at the 

 sides (at any rate in the males), most densely and minutely 

 granulated (the granules, however, being almost obsolete towards 

 the suture), crenate- striated, the interstices with a row of minute 

 tubercles down each, which are obsolete near the suture and in 

 front. Antenna Siud %5 long; the former (especially towards 

 the extremity) and the tarsi of the latter somewhat fuscescent. 



The present large Helops, the discovery of which is due to 

 Mr. Bewicke, is well distinguished from all the other Madeiran 

 species by its elongate parallel outline (at all events in the 

 male sex) ; by its most closely punctured head and prothorax, 

 the latter of which is relatively longer, and with the anterior 

 angles more porrected, than is the case in either H, Vulcanus or 

 H. confertus, and also more scooped-out on either side towards 

 the base, which causes the posterior angles to be more or less 

 prominent or acute ; and by its very densely and minutely gra- 

 nulated elytra, the interstices of which have a row of small but 

 well-defined tubercles down each (though both granules and 

 tubercles are nearly obsolete towards the suture, particularly in 

 front). 



The H, arboricola is altogether narrower and more cylindric 

 than H. Vulcanus, and its prothorax is relatively longer and less 

 convex; nevertheless in actual length it almost equals that in- 

 sect. Its habits, however, are quite difi'erent; for whilst H, 

 Vulcanus is a maritime species, occurring beneath stones and 

 in fissures of exposed rocks towards the coast, H. arboricola 

 is found (like H. confertus) under the bark of trees in sub- 

 sylvan spots of intermediate elevations. Under such circum- 

 stances a single specimen was captured, first, by Mr. Bewicke, 

 during the spring of 1861, high up in the Ribeira de S. Luzia ; 

 and in April of the present year he again met with the species, 

 in another but very similar locality — in the Vasco Gil ravine. 

 Referring to this circumstance, in a letter lately received from 

 him, Mr. Bewicke remarks as follows : — " I took one a short time 

 ago, in a tree, up the Vasco Gil ravine ; Senhor Moniz and I 

 subsequently spent a day there and searched the whole vicinity, 

 but found nothing until we came to the original tree, where we 

 obtained three or four more. They were all of them beneath 

 bark, at a considerable height (about 10 or 12 feet) from the 

 ground. The H, confertus was very abundant in that tree, as 

 well as in most of the others ; and it is perhaps worthy of note 

 that the tree was in a very similar position to the one (in the 

 llib. de S. Luzia) in which I took the insect last year — namely, 



23* 



