INSECTA MADERENSIA. 513 



rendering wings unnecessary) ; their elytra are almost invariably joined together ; 

 theii- bodies are especially thick and subovate (or at least it is their tendency to 

 become so, their prothoraces being wider posteriorly than is usually the case in 

 the flower-infesting or metallic forms) ; and their four anterior feet are always 

 expanded in the males, — in which sex also the legs are peculiarly robust, and the 

 antennae are much elongated. Like the Sadri, they are excessively gregarious, — 

 clustering beneath slabs of stone (often in the utmost profusion), or secreting 

 themselves in the chinks and fissm-es of the mountain-summits. They most of 

 them emit, when captured, an impleasant odour (like a large proportion of the 

 Melasomes) ; and so pungent is this scent in one or two of the species, that their 

 presence may be frequently detected even before actually observed. 



389. Helops Vulcanus, TT'oll. (Tab. XII. fig. 1.) 

 H. subovatus ater subnitidus confertim punctulatus, prothorace amplo convexo ad latera basin versus 

 siuuato (angulis posticis plus minusve subrectis), elytris rugosis profunde crenato-striatis, inter- 

 stitiis apicem versus seriatim tuberculatis, antennis pedibusque robustis. 

 Var. «. latus, protborace ad angulos posticos subrecto. (Ins*. Deserta Borealis et Grandis.) 

 Var. /3. vix angustior convexior, protborace ad latera valde sinuato angulis posticis rectis. (Ins. Ilheu 



de Fora.) 

 Var. y. angustior minor oblongior et profundius punctatus, prothorace paulo longiore ad angulos 



posticos subrecto. {Ilheo de Fora ; status aberrans.) 

 Var. 8. protborace ad latera minus sinuato angulis posticis subobtusis. {Madera ; per oram mari- 

 timam.) 

 Long. Corp. lin. 6i-I0. 



Habitat sub lapidibus et in rupium fissuris Maderse, insularum adjacentium necnon Desertarum, prae- 

 sertim mox supra oram maritimam, uon infrequens : in summo Desertee Grandis atque in insula 

 Ilheo de Fora dicta prsedominat. 



H. subovate, deep black, slightly shining, closely and rather coarsely punctulated. Prothorax large 



and convex ; widest a little before the middle, and with the sides sinuated behind, — causing the 



posterior angles to be more or less of right angles. Elytra rugose, or transversely wrinkled ; 



deeply crenate-striated ; the interstices having each a row of tubercles, apparent behind but 



obsolete in front. Legs and antennae exceedingly robust, especially in the males. 

 Var. a. slightly wider and larger than the other varieties. Prothorax with the posterior angles 



almost right angles, but with the anterior portion scarcely so much expanded as in the var. /3. 



(The state peculiar to the Northern and Central Dezertas.) 

 Var. |3. a trifle narrower and more convex than the Dezertan specimens. Prothorax with the sides 



greatly sinuated behind, and with the posterior angles right angles. (Typical on the Ilheo de 



Fora.) 

 Var. y. the narrowest in proportion of the whole, being more oblong (or subcylindi-ical), also smaller 



and rather more deeply punctured ; with the prothorax comparatively elongated, and its posterior 



angles almost right angles. (Ilheo de Fora ; abnormal state.) 



3u 



