112 INSECTA MADERENSIA. 



anticc Icviter angustatum ct temiissimuin, utrinquc in lobum medium lateralem productum. Ligula 

 lata biloba, lobis rotundatis ciliatis. Pedes cursorii, subgraciles : femoribus libusque compressis, 

 his apice lenter spinulosis ct calcariis internis sat distinctis munitis : tarsis (II. 9 e. 9/. 9^) 

 articulo tertio bilobo, quarto minutissimo ; posticis (II. 9 e) elongatis, articulo secundo longiusculo. 



Olibrus was established by Ericbson, in 1848, m. order to contain those members 

 of Phalacrus which had the terminal joint of their maxillaiy palpi slightly robuster 

 than is the case with the ordinary representatives of the group, their tibial spurs 

 distinctor, and their two hinder tarsi somewhat more produced, and ■nith the 

 second articulation the longest. To these characters however I think the con- 

 struction of the mentiun should certainly be added, since, if my observations be 

 correct, it is the most invariable, and therefore the most important, feature which 

 the several species possess. Thus, in all the Olibri which I have dissected it is 

 narrowed anteriorly (where it is extremely thin and membranaceous), and has the 

 sides produced, about the middle, into a large rounded lobe ; whereas in the true 

 Phalacri it is broader in front than behind, truncated at the apex, and altogether 

 more transverse and of a thicker textm-c. In fact, with the exception of the 

 peculiarity of their mentum, it seems to me that the Olibri, as defined by Erich- 

 son, are apt to merge almost imperceptibly (especially as regards the spines of 

 theu- tibia?) into the normal Fhalacri, — of which the common Em-opean P. coruscns 

 is supposed to be the type : and it is far from improbable moreover that in some 

 of the forms an intermediate state of mentum may exist likewise, — in which case 

 none of the elements of Olibrus can be considered as sufficiently constant to be of 

 more than sectional significance. They are insects which are subject to con- 

 siderable instability, both in size and colour, and are consequently in many 

 instances extremely difiicult to determine, specifically. There are few genera 

 indeed amongst the entire Coleoptera in which an extensive series of examples 

 is more positively required in order to investigate the species aright, and to 

 discover tlie boundaries between which some of them would appear to range. 

 They are almost exclusively of flower-infesting habits ; and rim with the utmost 

 agility. They are excessively gregarious, and may usually therefore be taken in 

 large numbers where they exist at aU. 



89. OUbnis Cmerariae, Woll (Tab. II. fig. 9.) 

 O. subrotundato-obovatus subviridescenti-niger nitidus, capite prothoraceque rufo-testaceis, elytris 



substriatis ad apicem testaceis, singuli striis duabus suturam versus reliquis paulo distinctioribus, 



antennis pedibusque testaceis. 

 Long. coq). lin. I^. 



Habitat florcs Cineraria aurita { = Senecionis Maderensis, De Cand.) in rupibus Maderse crescentis, 

 proosertira per partem sylvaticam aestate, rarissimus : ad Cruzinhas est paulo copiosior, qua Julio 

 incunte a.d. 1850 plurima speciniina collcgi. 



