272 



CURCULIONIDJ5. 



1851. It is extremely interesting geographically, through the fact 

 of its being very closely allied to the A. argillosus from Teneriffe. 

 Although greatly resembling that species, however, both in size and 

 general aspect, I do not think that it would be safe to treat it as an 

 insular state of it at all events until a more accurate knowledge 

 has been acquired as to how far these numerous Atlantic Acdlles are 

 subject to external modification through the long-continued action of 

 surrounding influences *. 



752. Acalles argillosus. 



Acalles Brgillosus, Schon., Gen. et Spec. Cure. iv. 327 (1837). 

 Tylodes scaber, Srutte, in Webb et Berth. (Col} 72, pi. 1. f. 14 (1838). 

 Acalles argillosus, Woll, Cat. Can. Col 283 (1864). 



Habitat Canarienses (Ten., Gom., Hierroi), intra caules Kleinice tierii- 

 folice, De Cand., degens. 



A large Canarian Acalles, which seems to undergo its transforma- 

 tions within the stalks of the Kleinia neriifolia. I obtained it from 

 the hollow branches of the Kleinia at Taganana in Teneriffe ; and the 

 Messrs. Crotch met with it abundantly, under similar (and indeed 

 under no other) circumstances, in Gomera and Hierro ; and even 

 Messrs. Webb and Berthelot, who seldom give us any information of 

 either local or general interest, record its capture " dans les branches 

 et les vieux troncs du Cacalia Kleinia ; " so that there can be little 

 doubt that it is attached exclusively to that singular plant. 



The A. argillosus is eminently musical ; but in all probability this 

 is owing more to its large bulk, and its consequently increased power 

 for stridulation, than to any specific peculiarity of its own. In the 

 * Ann. of Nat. Hist.' for July 1860 I gave a full account of the 

 manner in which this fine Curculionid generates its " anal song; " 

 but I have subsequently ascertained that all the Acalles are able to 

 perform more or less audibly, according to their respective sizes and 

 capacities. Since the publication of the paper above alluded to, Mr. 

 F. Smith has tested certain British species, and finds them to be 



* The A. Neptunus differs from the argillosus, mainly, in its scales being yel- 

 lower (or of a much less chalky white), in its rostrum being rather flatter and 

 less keeled in front, in the third articulation of its feet being a trifle less 

 expanded, and in its prothorax (when denuded of the scales), although very 

 coarsely and densely punctured, appearing scarcely so deeply or so thickly punc- 

 tured, or so decidedly opake, as is the case in that insect. Its elytra likewise are 

 more or less ornamented posteriorly with irregular black spots, or broken lines, 

 which do not appear to exist in the argillosus ; and the first joint of its funiculus 

 is perhaps a little more elongated, being more decidedly longer than the second 



one. 



