166 INSECTA MADERENSIA. 



exceedingly short, monilrform, and robust, becoming sensibly thicker toyvards their apex. Legs 

 rufo-testaceous. 



An exceedingly Avell-cleflned species, — its anteriorly subaciiniinated outline, in 

 conjunction with the excessive shortness and robustness of its antenna?, the opake 

 and greatly wrinlded (though tnqmnctured) siu-facc of its head and prothorax, and 

 its raised elytral striae, at once distinguishing it from all the Lcemophlcei -nith 

 which we have here to do. Like the L. axillaris, it is hitherto iinique, the 

 example from wliich the above description has been cbaA^Ti out having been cap- 

 tured Ijy myself, in company 'o-ith that insect, at the Ribeiro Frio, during August 

 1850. 



Genus 56. SILVANUS. 



Latreille, Gen. Crust, et Lis. iii. 19 (1S07). 



Corptis minusculum vol par\'uni, plus niinusvc elongatum angustatum et dcprcssum : pruthorace 

 angulis (prasertim anticis) sa;pius valde productis, ad latera plus minusve crenulato-dentato : 

 alis amplis. Antenna spepius subclavatse, articulis inimo, secundo et tertio longitudine sub- 

 sequalibus (prime sat robusto), quarto ad scptimum subglobosis, octavo ])aulo niinore, rcliquis 

 clavaui plus minusve obscui-am laxam triarticulatam efficientibus. Labrum transvcrsum, antice 

 integrum ciliatum. Mandibulee validaj acutse, infra apicem profunde excisse ciliatse. Maxilla 

 bilobie : lobu externa lato, apice valde pubesceuti : interno minuto brevi angusto pubesccnti. 

 Palpi maxillarcs articulo primo angusto flexuoso, sceuudo et turtio crassis subtcqualibus, ultimo 

 elongato fusiformi basi truncato : labiates articulo primo minutissimo, secundo et idtimo elougatis 

 longitudine subsequalibus (illo subclavato, hoc subfusiformi basi truncato). Mentum transvcr- 

 sum, antice excavato-emarginatum. Licjula ampla subquadrata, apice valde pilosa. Pedes 

 robusti : tarsis articulis primo, secundo et tertio magnis suba^qualibus (tertio cordato), quarto 

 minutissimo. 



Not to mention minor points of distinction, which Avill be readily gathered from 

 the above diagnosis, the genus Silcamts may be kno^\■n from Lcemophloeus by its 

 usually less depressed form, by its shorter and more clavated antenna?, and by the 

 structiu'c of its mandibles and tarsi, — the last of which are pentamerous in both 

 sexes, and have their basal articulation comparatively large {iiot being percei)tibly 

 more abbreviated than either of the following two), and their fourth one extremely 

 minute. In their oral organs, as well as in their habits, the S'lhani approach veiy 

 closely to the Cri/ptophagi (from wliieh indeed one or tAvo of the less tj-pical species 

 are not, at first sight, very easily separable), — thus constituting a vciy natural 

 link between the Cryptophagidce and the CucttJidcB, to both of which they are so 

 intimately related that it matters but little, I conceive, to which of those families 

 we choose to assign them. The most essential featm-es in wliich they recede from 

 C'rfiptopliayus, apart from their narrower, flatter, and generally more sculptm'cd 

 liodies, are the longer and subaciuninated terminal joint of their palpi, and the 

 construction of theii' feet, — those of the Cryptophagl being heteromerous in the 



