Ptinida of the Canary Islands. 191 



of the iTientum ;* but, as tlioiigh finding it out for (apparently) the 

 first time whilst enunciating Nipius, he makes the observation in a 

 foot-note, " Cette de7it existant dans tous les Ptiniores, je n'en ai 

 pas fait mention dans les genres precedents" ! And, furthermore, 

 (with respect to Niptus), although the genus appears to possess 

 sufficient characters in the shape of its eyes, femora, and the 

 under-parts of its body, he does not even refer to them, but 

 founds his diagnosis on two or three imaginary differences (for, 

 according to the dissections now before me, they are strictly 

 " imaginary ") in the details of its mouth. Then, in Trtgonogemus 

 M. De Boieldieu gives scarcely any characters at all, and speaks 

 ofthementum as " carre, comma dans tous les Ptiniores;" but 

 certainly he must have been aware (since it appears he had un- 

 doubtedly seen the menta of, at any rate, Niptus and Gihb'mni) 

 that the shape of that organ would be better expressed by almost 

 any term that could be selected than square. Besides, the only 

 real peculiarities of the group — namely, the obsolete scutellum, 

 the excessive shortness of the penultimate abdominal segment, the 

 very distant posterior coxae, and the form and brevity of the 

 metasternum — are not so much as glanced at ! Of the cosmo- 

 politan Mezium there is no generic formula added of any kind, 

 the author stating that he was unable to procure a specimen for 

 dissection ! Whilst in his figured details of G?66iMm he is entirely 

 wrong : for not only has he made the inner lobe of the maxillse 

 much too abbreviated, and the apex of the raentum too acute ; 

 but he has, likewise, drawn the basal joint of the labial palpi 

 straight and short (instead of long and curved) ; and (as is equally 

 the case in Niptus) he has entirely omitted the singularly-pro- 

 duced shoulder of the maxillary stipes which projects outward 

 (in all the members of the Ptinidce) into an elongated process 

 immediately below the insertion of the palpus. This last feature, 

 which is a very important one, he has not alluded to in any of the 

 genera. 



But, having thus criticized the structural details given by 

 others,'!' let us see what the characters of the group really are. 



* Even Prof. Lacordaire, in his admirable " Genera des Col6opteres," omits 

 all notice of this process, speaking of the mentum as " transversal, ]6gerement 

 6f:hancr6, ses angles anterieurs plus ou moins aigus." 



f Since finishing the present Paper I have received the Part of the " Genera 

 des Coleopt. d'Europe," in which iM. Jacq. Duval has treated the Ptinida, and 

 I am bound to add, that his details are on the whole remarkably accurate and 

 satisfactory. I think, however, he does not give sufficient prominence to certain 

 peculiarities, — as, for instance, the arcuation of the basal joint of the labial palpi 

 (which is no straighter than is the case in the maxillary pair), the elongated 



