192 Mr. T. Vernon Wollaston on the 



We will take the orgnns seriatim.* Akliough more or less pilose 

 at its apex, the shape of the upper-lip is almost invariable, — being 

 nearly square, a little excavated at the tip, and with its anterior 

 angles slightly rounded. -|- The mandibles are shortly-acute (and 

 simple) at their extreme apex, and from thence oblique to nearly 

 the middle of their inner edge, — where the sudden turn which the 

 direction of the latter takes, from thence to the base, occasions 

 the»shaping-out of a blunt central angle, or tooth. This structure 

 is, also, nearly invariable, — the slightly obtuser mandibles of 

 Piarus, and the still more obtuse ones of Casapus being the only 

 exceptions to it (and even those merely in degree) with which I 

 am acquainted. The maxillae are always bilobed ; the outer-lobe 

 being small and narrow, and the inner one rather shorter and 

 broad, and both of them densely pubescent. A curious feature, 

 however, exists in the stipes of the maxillae, which is produced 

 outwards into an elongated, more or less blunt, shoulder-like 

 process (usually furnished with a few enormously long hairs) im- 

 mediately below the insertion of the palpus. Both the maxillary 

 and labial palpi are remarkable for the comparative great length, 

 slenderness and curviture of their first articulation (a peculiarity 

 which attaches to every member of the family which I have dis- 

 sected) ; whilst the terminal one is somewhat elongate-fusiform, 

 being truncated at its base and acuminated at its apex. This 

 latter character is likewise universal in all the Ptinidce which I 

 have yet examined, except in the Canarian genera Casapus and 

 Dignomus, — both of which have the ultimate joint of their labial 

 palpi anomalously scooped-out at its tip. Then comes the men- 

 tum, which is perhaps the most curious, no less than the most 

 constant, of the parts of the mouth. By far its larger portion, 



shoulder-like process of the ilipes of the maxillae, and the excessive siiortness in 

 some genera of the penultimate segment of the abdomen. He is scarcely correct, 

 too, in calling the ligula " petite ;" for it is decidedly elongate (though narrow), — 

 as indeed is evident from the fact that it projects considerably beyond the enor- 

 mous central-process of the menlum. When detached from the latter, its length 

 is seen to be very considerable. 



* I may mention here, that the species which I have dissected (some of them 

 twice over) are the twelve following : Casapus Bonvouloirii and subcalnus, Dig- 

 nomus gracilipes, Ptiniis 6-punctatiis, Niptus hololeucus, Meziiim sulcatum, Gih- 

 hium scotias, Nitpus gonospermi, Sphcericus ulhopiclus, Piarus basali s a.nd Piotes 

 fasciata and vestita ; which, it will be observed, are all the acknowledged genera 

 except Hedobia and the South American Trignnngenius. 



t On account of the pile with which it is sometimes clothed, the anterior emar- 

 gination of the labrum often appears at fust sight considerably shallower in some 

 genera than in others ; but when viewed through a transparent medium (on 

 mounting them in balsam) [ find it nearly the same in all. 



