INSECTA MADERENSIA. 435 



rently, has not extended itself even over the Dezerta Grande (where there are no 

 external obstacles to bar its progress) ; but retains the very position which in all 

 probability constituted its original centre of dissemination at the remote period of 

 time when this ancient continent received its allotted forms. Judging from the 

 slowness with which creatures of such habits must necessarily (under any circum- 

 stances) be diffused, it is at least unlikely that the present one could have circu- 

 lated far, when the now submerged portions of that region began to give way ; 

 and hence it is not impossible that the Southern Dezerta with the adjacent part 

 (then united to it) of the Central one may have embraced the lohole area of its 

 actual primiEval range, — the remains of which (though they be now separated by 

 a channel) it still continues to occupy, and from which, even where physically un- 

 impeded, it has never roamed. 



Sectio IX. PHYTOPHAGA. 

 Fam. 38. CRIQCERID^. 



Genus 143. LEMA. 



rabricius, Ent. Syst. v. Swppl. 90 (1798). 



Corpus parvum, parallelo-oblongum, interdum Isete coloratum : capite porrecto ; oculis subintegris : 

 prothorace elytris angustiore, postioe ssepius constricto : scutello apice valde truncate : alts amplis. 

 Antenna robustfe filiformes, vel apicem versus vix incrassatse, articulo primo robusto breviusculo, 

 secundo brevissimo, tertio, quarto et quinto longitudine variabilibus, reliquis subsequalibus lati- 

 tudine plus minusve leviter crescentibus. Labium conieum, subquadrato-transversum, apice vix 

 integrum. MandibuliB validae cornese latae, apice acutfe bifidse, luargine interne ssepius integro. 

 Maxillce bilobte submembranacese, lobis valde ciliatis. Palpi filiformes ; maxillares articulo primo 

 parvo, secundo majore subclavato, tertio buic paulo breviore, ultimo elongato-oblongo apice 

 obtuso ; lahiales articulo primo parvo, secundo majore crassiore, ultimo subovato apice obtuso. 

 Mentum corneutn subluniforme, antice profunde emarginatum. Ligula submembranacea, apice 

 setosa Integra. Pedes leviter elongati : unguiculis basi connatis. 



Both Lema and Crioceris may be known from the rest of the Phytophaga here 

 described by their comparatively elongated, parallel forms, and by their sub- 

 cylindrical prothoraces, — which are much narrower (especially at their base) than 

 the elytra. They are genera of a wide geographical range, occurring in nearly all 

 parts of the world. The insects of which they are composed are principally gaily- 

 coloured, and are exclusively attached to plants (particularly those of a succulent 

 nature), — on which, both in their larva and perfect states, they subsist. The species 

 are exceedingly numerous, — M. Lacordaire, in his Monographie des Fhytopihages, 

 enumerating no less than 273 of the former, and 43 of the latter. 



3 k2 



