INSECTA MADERENSIA. 259 



Fam. 30. PTINID-ffil. 



Genus 93. PTINUS. (Tab. V. fig. 4, 5 et 6.) 

 Lmn»us, Si/sf. Nat. ii. 565 (1767). 



Corpus parviira, oblongum vel sphsericum, durum, plus minusve pubescens vel squamosum : capite 

 deflexo, sub prothorace vix abscondito : scutello modo distincto, modo baud observando : pro- 

 thorace vel gibboso ad basin constricto, vel convexo : alls modo amplis, modo obsoletis. Antenna 

 plus minusve approximatpe, aut filiformes aut siibclavatse, articulo prinio robusto, seeundo vix 

 breviusculo, reliquis vel Eequalibus ultimo elougato-ovato, vel latitudine sensim crassioribus 

 ultimo ovato. Lahruui corneum transversum, antice pilosum leviter emarginatum. Mandihula 

 maguse cornefe validfe latoe subtriangulares obtusse, intus medio dente obtuso instructse. Maxilla 

 bilobffi, lobis submembranaceis apice pubescentibus ; externa leviter incurvo ; interno paulo 

 breviore latiore. Palpi subclavati; maxillares articulo primo vel parvo, vel (ut in Mezio et 

 Gibbio) longiusculo subflexuoso, seeiuido et tertio crassioribus subsequalibus, ultimo clongato 

 robusto fusiformi apice acuminato ; labiates articulo primo gracili, seeundo lougiore crassiore, 

 ultimo robusto subovato apice vix acuminato. Mentum corneum, modo subrotundatum, modo 

 elongatum antice acuminatum. Ligula membranacea elongata, apice dilatata Integra pilosa. 

 Pedes longiusculi subcontractiles, graciles vel robusti : femorihus apicem versus subito incrassatis : 

 tarsis modo longiusculis articulis quatuor baseos (primo longiusculo) longitudine leviter decres- 

 centibus, modo breviusculis articulis quatuor baseos (prsesertim in anterioribus) subsequalibus ; 

 quinto vel longiusculo vel breviusculo unguiculis simplicibus munito. 



The great diversity, both in structure and outward contour, of the Ptini renders 

 the group an extremely intricate one to define ; and the gradual manner ia which 

 many of its variations are apt to merge into each other makes it almost equally 

 useless, without an intimate acquaintance Tvdth all the forms hitherto described, 

 to attempt to dissever any portion of it from the remainder. Yet some of the 

 species do nevertheless exhibit, in habits as well as detaU, such obvious differences 

 inter se, that it is possible that a careful examination of their oral organs, on a 

 comprehensive scale, might succeed in detecting sufiicient characters for generic 

 subdivision : but until this is done it would be lost labour to chalk out lines of 

 demarcation, — especially in a work like the present one, which, having but a few 

 memliers to deal with, must of necessity be confined withia very restricted bovmds. 

 StUl, the Madeiran representatives (from the want, it may be, of intermediate 

 links to unite them) do at any rate arrange themselves imder two clearly-defined 

 heads ; the fii-st of which, like the ordinary Ftini of central and boreal Europe, 

 has the body comparatively elongated and pubescent, and for the most part 

 winged, the prothorax more or less gibbous (or nodulose) in front and transversely 

 contracted behind, the scutellum large, and the antennae and feet slender and 

 filiform (the last of which, moreover, have their basal joiat perceptibly longer 

 than any of the folloAving three) ;— whilst in the second (a most abundant modifi- 

 cation along the southern Mediterranean limits) the shape is altogether more 

 spherical, the surface more or less densely scaly (but free from pile), the body 



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