130 INSECTA MADERENSIA. 



primo interdum (in sexu masculo, ut opinor) in lobuni spiniformeni plus minusve obtusum 

 subtus producto (III. 4/, et 6), quarto valde elongato flexuoso subclavato, unguicuUs simplicibus 

 munito. 



There is perhaps no Madeiran genus more interesting geograpliically, or better 

 defined, than Tarphius. In its general contour and habits, and in its 4-jointed 

 tarsi, it is intimately related to such groups as Diodesma, Coxelus, ColoMcus and 

 Synchita, though with abundant distinctive characters of its O'vro.. It is with the 

 first of these howcA'er that it would seem to possess the strongest afl&nity, since it 

 not only approaches it in the details of its antennae and mouth, but likewise in its 

 freedom from wings. Nevertheless, in many of its most important features it 

 recedes from the whole of them, and in none more so than in the structiu-e of 

 its feet, — which have a tendency in (what I believe to be) the males of most of 

 the representatives to have theu" l)asal articulation produced beneath into a more 

 or less acute spiniform lobe, and which in some instances is so exaggerated as 

 to be at once conspicuous even to the naked eye. As regards their outward 

 configuration, the Tarphil are either brightly maculated on theu- elytra or else 

 armed with nodules, — the one state appearing to be normal and the other 

 aberrant. T\Tiere the patches are well-marked* there is seldom any indication 

 of protuberances ; but, as the former are gradually removed the latter begin to 

 arise t, — until, at last, in those species | where the patches ai'c altogether cither 

 evanescent or suffused, the projections have attained theii- maximum and become 

 detached humps (concolorous with, the rest of the body) in the exact positions 

 occupied by the sjiots. These prominences however are generated in a rather 

 singular manner, and should perhaps, more strictly, be defined as broken ridges 

 than isolated nodes; for as the blotches vanish the alternate interstices (which 

 have always a faint tendency to elevation) become not only more perceptibly raised, 

 but, at the same time, interrupted, especially behind, — thus lea^dng larger or 

 smaller gibbosities, which have every appearance, at first sight, of having been 

 independently developed. In rare cases § indeed there is a pale tinge even on the 

 nodules, but in such the colour is more or less distributed over the entire elytra 

 also, — diluting their surface and giving them a somewhat transparent aspect. 

 ^Vnother modification || occurs, in which the short rigid pubescence with which the 

 insect is clothed takes a partially golden tinge, and im^iarts to the himches, even 

 in the absence of under-patches, a dirty-yello^^■ish cast, — so keeping up the analogy 

 of the latter in a very peculiar way. 



The males of the Tarphii, if I be right in my identification of them, are for the 

 most part a little smaller than the females ; and, since tliis is in accordance mth 

 what we observe throughout the Coleoptera generally, it is probable, thus far at 



* E. g. T. rotundafus, Lauri, and Lowei. t T. echinatns and compactus. 



X T. testudinalU, nodosus, and rugosus. § T. cicatricosus, truncatus, and hrevicollU. 



II T. nodosus and testudinalis. 



