450 Mr. T. V. Wollaston on Additions to Madeiran Coleoptera. 



striate-punctate, the punctures being very large ; the interstices 

 rather wide and flattened, and with a row of minute punctules 

 down each. Antennae and tarsi rufo-ferruginous ; the femora 

 and tibia scarcely paler than the rest of the surface ; the body 

 beneath densely and deeply punctured all over. 



The discovery of the present insect is due to the researches of 

 Mr. Bewicke, who has captured several specimens of it, in com- 

 pany with the Rhyncolus calvus, amongst rotten wood, at the 

 Praia Formosa, near Funchal. 



Genus PENTARTHRUM. 

 Wollaston, Ann. of Nat. Hist. ser. 2. vol. xiv. p. 129 (1854). 



In their outward facies the two insects described below are 

 moulded less on the true Cossonus type than the curious little 

 Wood-feeder, detected in the West of England, for which I origi- 

 nally established, in 1854, the genus Pentar thrum. Neverthe- 

 less, since they clearly belong to this immediate section of the 

 Curculionida, and agree with the P. Huttoni in possessing the 

 anomalous character of a 5-jointed funiculus, I have preferred 

 regarding them as congeneric with the British species to erecting 

 an additional genus for their reception. In their convex, gla- 

 brous bodies indeed, and general contour, they are more sug- 

 gestive of Caulotrupis, perhaps, than of Mesites or Cossonus ; 

 whilst from the Pentar thrum Huttoni they recede (especially, how- 

 ever, the P. Monizianum) in their more apically-inserted antennse 

 and less straightened rostrum, as well as in their excessively 

 minute and almost obsolete eyes. In the P. Monizianum indeed 

 there is scarcely any trace, with an ordinary lens, of the organs 

 of sight ; but when the head is viewed beneath a microscope, 

 one can perceive (though not without some difficulty), adjoining 

 the upper- edge of the extreme termination of the rostral groove, 

 5 or 6 closely-set depressed tubercles, within a small enclosure, 

 which are clearly the rudiments of an eye ; but so abortive 

 are they, that there can be but little doubt that the insect must 

 be practically blind. In the P. Bewickianum these rudimentary 

 eyes are a trifle more prominent, and therefore perceptible ; but 

 as regards their development, they do not appear to be at all 

 more perfect. 



I. Antenna longiuscula graciliuscults, rostri apicem versus insert a, 

 articulis funiculi inter se laxis, capitulo abrupto ovato. Rostrum 

 ad antennarum insertionem sensim dilatatum. 



Pentarthrum Monizianum, n. sp. 



P. piceum vel rufo-piceum, nitidum ; prothorace profunde punctate ; 

 elytris ellipticis leviter striato-punctatis (punctis minoribus), in- 



