516 INSECTA MADERENSIA. 



hitherto observed, to Madeu-a proper; where it occui's at nearly all elevations, 

 though more particiilarly below the altitude of 2000 feet. It is the only member 

 of the genus included in our fauna in which a subcortical tendency wovild appear 

 to be indicated : yet, nor mall y, I believe that even it is extra-sylvan, since it is 

 imquestionably cormnoncr beneath stones than bark. It varies a little according 

 to the altitude at which it is found, being usually deeply striated and rugose on 

 its lower, but sulipicescent and much more lightly sculptiu'cd on its upper limits. 

 I have taken specimens indeed on the Pico lluivo and on the mountaia-plain of 

 tlie Fateu'as which are so far diminished in roughness as almost to resemble, at 

 first sight, the H. Pluto ; nevertheless the more roimded edges of their (less 

 anteriorly-acuminated) prothorax, in conjimction with the tubercles (Avhich are 

 never absent) on the hinder region of their elytral interstices, will always succeed 

 in distinguishing even such examples as these, on fiu'ther examination, fi-om that 

 species. 



391. Helops Pluto, WoU. (Tab. XII. fig. 3.) 



H. elliptico-ovatus ater (vel niger) nitidissimus confertini punctulatus, prothorace antice acuminato ad 

 latera oblique-subrecto, elytris leviter crenato-striatis, antennis jjedibusque paulo brevioribus 

 fuscescentibus. 



Long. Corp. lin. 3^-5. 



Habitat sub lapidibus Maderse (a 3000' s. m. usque ad summos montes ascendens), tempore hiberno 

 et veniali vulgaris. 



H. elliptical-ovate (being about equally acuminated before and behind), deep black, exceedingly 

 shining, and closely but rather finely punctulated. Prothorax narrowed in tront, the widest part 

 being at the extreme hinder margin ; and with the sides nearly straight (though obhque), and 

 the posterior angles rather acute. Elytra scarcely at all roughened, and hghtly crenate-striated ; 

 the interstices having no appearance of the hinder tubercles which are more or less evident on so 

 many of the other species. Leys and antenna somewhat shorter comparatively than those of the 

 H. confertus, and more or less brownish-piceous or fuscescent. 



An exceedingly distinct Helops ; and readily known from the remainder of the 

 genus here described l)y its elliptical outline and by its brightly shining and com- 

 paratively smooth surface, — which has no ap2:)earance of the hinder elj-tral 

 tubercles which are so perceptible in most of its allies. Its j)rothorax also is more 

 attenuated in front, and has the sides (although oblique) straighter, than is the 

 case in any of the other species. It is peculiar to lofty altitudes, where however 

 throughout the winter months it is remarkably abundant, — occm-ring beneath 

 stones on the exposed grassy slopes, from about 3000 feet above the sea to the 

 extreme summits of the peaks. In the elevated district between the Pico da Lagoa 

 and the Pico dos Aricros I have observed it in the utmost profusion during the 

 early spring ; and I have likewise captui-ed it on the upland plain of the Paul da 



