28 INSECTA MADERENSIA. 



in its largely developed ^ings it recedes, I believe, from e-\-ery Pristonycluts yet 

 described, whilst its straightened and slender tibia?, in both sexes, will serve, 

 additionally, to distinguish it from the P. subcyanens, in which the intermediate 

 and hinder pair (especially the former) are decidetlly curved, as well as more 

 densely ciliated towards their internal ajiex. The claws, moreover, of the P. alatus 

 are more powerfully serrated at then- base than is usual in the other representatives 

 of the genus. It does not appear to be a very abundant insect in Madeii'a, although 

 pretty generally distributed along the southern coast in positions sKghtly elevated 

 above the shore. On the liills between Machico and Sancta Cruz I have captm-ed 

 it, not uncommonly, diu'ing the winter months ; and it has been, likewise, taken 

 by Professor Heer in the llibeu'O Secco, near Eunchal. In Porto Santo it is com- 

 Ijaratively plentiful, where, at the end of December 1848, I obtained it in con- 

 siderable profusion from the vicinity of the Cidade. 



Genus 11. CALATHUS. 



Bonelli, Observ. Ent. i. tah. sgn. (1809). 



Corpus mediocre, elongato-ovatum, plcrumque depressiim : prothorace subquadrato, antice ssepius 

 angustato : alis (in tj-jiicis amplis, sod in speciebus Maderensibus) obsok-tis. Antenna filiformes, 

 capite prothoraceque paulo longiores, articulo primo sequentibus robustiorc, secundo bre\i, tertio 

 primo multo longiore. Labrum quadi-atum, antice leviter emarginatum et setis paucis longissimis 

 instructum, angulis anticis rotundatis ciliatis. Mandibula breves incurvre acutte, intus basi den- 

 ticulatEG. Maxilla biloboe : loho externa palpiformi biarticulato : interna acuto incurvo, apice 

 uncinate, intus valde ciliato. Palpi filiformes, articulo ultimo subfusifonni-truncato. Mentum 

 transversum, antice profunde emarginatum et dcnte medio bre\-i bifido instruetum. Ligula 

 cornea, apice truneata pilisqiie diiobus longissimis aucta ; parar/lossis menibranaccis, ei asqualibus. 

 Pedes longiusculi, graciles : farsis anticis in niaribus articulis primo, secundo et tertio le\iter 

 dilatatis, subtriangularibus : unguiculis valde serratis. 



The distinctions between the present genus and the last have been already 

 pointed out,— theu' main difference, so far at least as theii" oral organs are con- 

 cerned, consisting in the form and development of their respective paraglossae, 

 and the consequent modifications in the general aspect of then- labia. So greatly 

 indeed, in the parts of theu" mouth, do the whole of these immediate groups 

 resemble each other, that both Calathus and Pristouychits approximate almost as 

 much to Argntor as they do inter se; and, in fact, if that genus could be severed 

 from Ptei'oslichits, it would constitute, in the structure of its trophi, a very gradual 

 passage between the two, since its paraglossae are shorter and less porrccted than 

 those of tlic latter, but more developed than those of the former, — wliilst in the 

 truncation of their ligula? the whole three are almost coincident. Externally how- 

 ever both Pyistoiiychits and Calathus recede very e"\"idently from Argvtor, though 

 especially perhaps in having their fore-tibitc and male tarsi less dilated than is the 

 case Avith the latter and its allied groups. The Calathi reside principally beneath 



