326 INSECTA MADERENSIA. 



§ II. Femora (jprcesertim antica) minus fortiter dentata : tihics rectw. 



249. Ceutorhjrnchus quadridens. 

 C. nigcr siibdepressus cinerco-squamosus, prothorace profunde canaliculato, clytris obtriangulari- 

 quadratis macula subscutcllari diluto-albida ornatis, pedibus cinereo-Lrroratis, geniculis, tibiis ad 

 apicem, tarsisque rufo-testaceis, 

 Mas, antennis paido propius apiccm rostri (ut solet in multis Curculionibus) insertis, et tibiis pos- 

 terioribus ad apicem internum in uncum excurvatum productis. 

 Long. Corp. lin. 1^-1 1. 



Curculio quadridens. Panzer, Fna Germ, xxxvi. 13 (1796). 



Ehynchanus Boraginis, Gyll. (nee Fab.) Ins. Suec. iii. 227, et iv. 594 (1813 et 1828). 



JSTedi/m Borraginii, Steph. 111. Brit. Ent. iv. 35 (1831). 



Cetitorln/nchus quadridens, Sehon. Gen. et Spec. Cure. iv. 534 (1837). 



Habitat in cultis Madera;, prsesertim in vinctis et hortis culiuaribus, a>state uou iufrequens : etiam in 

 ins. Deserta Grandi, meuse Maio exeunte a.d. 1850 (a jNladcra illuc forsan iutroductus), cepi. 



C. black, more or less besprinkled or clotted (especially beneath) with cinereous or ashy scales, and 

 somewhat depressed. Head strongly keeled behind, but not at all so in front. Prothorax 

 coarsely and rather remotely punctured ; with a wide and deep dorsal channel, especially behind, 

 a distinct tubercle on either side of its disk, and with its front margin greatly elevated. Elytra- 

 obtriangular-quadrate, and very slightly abbreviated at the apex ; with a more or less well-defined 

 patch, at the base of the suture (immediately behind the scutellum), more thickly beset than the 

 rest of the surface with ashy scales. Legs more or less clothed with ashy scales or hairs : femora 

 with a very small and obscure spine beneath, that on the anterior pair (particularly of the males) 

 being almost obsolete : libice straight, with their extreme base, and a larger portion at their apex, 

 together with the tarsi and the antenna (except the apical half of then- club, which is ferruginous), 

 rufo-testaceous. 

 Male, with the antenna; inserted rather nearer to the apex of the rostrum than is the case with the 

 female (a character which obtains, more or less, throughout a large portion of the Curculionida) ; 

 and with the four hinder tibia; produced at their inner apex into an outwardly-curved hook. 



The C. quadridens, so extremely abundant tliroug-hout the whole of Europe, 

 may be known from the other Madeii-an Cenlorhunehi by its somewhat dejiressed 

 form and deeply punctured prothorax, by the cinereous or ashy scales with which 

 its upper sm-face is more or less besprinkled (and which are condensed into a patch 

 about the scutellum only), and by the acute, outwardly-curved hook with which 

 the inner apex of the four hinder tibiae of its males are furnished. The Madeiran 

 specimens differ from the ordinary ones in having the apex and extreme base of 

 their til)ite more distinctly testaceous. It occurs, dimng the summer months, in 

 cidtivated grounds of rather low elevations. I have taken it in the Rev. R. T. 

 Lowe's garden near Funchal, and in the vineyards of Santa Anna; as also, in 

 tolerable abimdance, at the end of May 1850, on the Dezerta Grande, — where in 

 all probability it has been accidentally introduced with culinary and other plants 



