622 INSECTA MADERENSIA. 



pimctulated prothorax and almost unstriated elytra, give it a character which it is 

 impossible to mistake ; whilst its extraordinary variableness in the depth of its 

 punctiu-es and its liability to intermutation between opacity and brightness (and 

 which moreover is in no way dependent on the sex) a^tU serve additionally to 

 discriminate it. It occiu's only (so far as I have hitherto observed) in Porto Santo, 

 — where however it is extremely abundant, diu'ing the winter and early sj^ring 

 (beneath stones), on the Campo de Baxo, and on the dry barren slopes and enclo- 

 sures in the immediate vicinity of the Cidade. It is essentially of low range ; and 

 in liabits would seem to be analogous to the Madeu-an H. cinnamomeus, although 

 ainmdantly distinct from it specifically. 



SectioXIL TRACHELIA. 

 Fam. 51. (EDEMERID^. 



Genus 176. STENAXIS. (Tab. XIII. fig. 2.) 



Schmidt, in Linn Entom. i. 87 (1846). 



Corpus mediocre, angusto-elongatum, pubescens, mollc ct plus miiiusve Ifcte coloratum : capite pro- 

 dueto ; oculis oblongis : prothorace parvo subcyliudrico, elytris angustiore, postice subcoarctato : 

 elytris apicem versus leviter attenuatis : alts amplissimis. Antenna in fronte prope oculos insertse, 

 filiformes, articulo primo vis robusto, secundo brevissimo, reliquis (e tcrtio elongate) lougitudine 

 paulatim vix decrescentibus. Labrum coriaceum subquadrato-transversum, antice vix emargi- 

 natum. Mandibulce longiuscula; subrectte, apice acutissima; bifidse, margiue interno membranfi. 

 angusta ciliata aucto, basi minutissime crenulato et ante basin fisso-sinuato. Maxilla bilobae, 

 lobis membranaceis, apice longe pencillato-pubescentibus obtusis. Palpi maxillares elongati, 

 articulo ultimo (in typica, sc. S. annulato, subsecui'iformi-cylindrico, sed in specie iladerensi) 

 subfusiformi-cylindi'ico : labiales e scapis ligulse connatis surgentes, articulo ultimo (in typic& 

 subsecuriformi-obconico, sed in nostr4) subfusiformi apice acuminate. Mentuni fere ut in Pec- 

 teropo vel Malachio, clongatum lateribus rotuudatis, antice et postice mcmbranaceum, in parte 

 media transversa coriaceum. Lit/ula tenuissimc membranacea, profuude biloba, lobis di\ergen- 

 tibus, apice inter lobos setis duabus mediis brevibus robustissimis instructo. Pedes elongati, 

 gracUes : tibiis ad apicem internum leviter bicalcaratis : (arsis heteromeris, articulo primo (prae- 

 sertim in posticis) elongate, pcuultimo bilobo subtus longe pubesccntc, ultimo lougiusculo ungui- 

 culis simplicibus munito. 



Although the insect from which the above diagnosis has been dra^vn out recedes 

 a little in the configm-ation of the ultimate joint of its palpi fi'om the Em-opean 

 S.annidata (the type, and hitherto sole exponent, of the group), stUl I have no 

 hesitation in referring it to Sienaxis, since in aU other essential particulars (as, for 

 instance, its produced head, ol)long eyes, the insertion of its antennae, its simple 

 femora, and the equality of its tibial spurs) it entirely coincides with it. Its only 



