612 INSECTA MADERENSIA. 



pubescence, — which however is somewhat darker on the head and prothorax than elsewhere. 

 Head with the anterior angles a little raised, and with the clypeus rounded in front. Protfiorax 

 subcordate, and with two longitudinal interrupted impressions on its hinder disk,— constituting 

 four somewhat obsolete fovcje. Elytra occasionally a little more diluted in hue towards their 

 apex, — though at other times apparently quite black. Antenna dark brownish-piceous, with 

 their base (and the palpi) a shade paler. Legs pale diluted-testaceous. 



The present minute Trogophlceus, which seems to differ slightly from all the 

 Em'opean species with which I am acquainted, would appear to be extremely rare, 

 — though, from its diminutive size, obscure hue and burrowing habits, it is of 

 course very liable to be overlooked. The only thi-ee specimens Avhich I have seen 

 were captured by myself in the north of the island dm-ing the summer of 1850,— 

 from off mud at the edges of a small stream at Santa Anna. 



(Subf. 7. OMALIADES.) 



Genus 211. OMALIUM. 

 Gravenhorst, Col. Mieropt. 116 (1802). 



Corpus parvum, lineaii-oblongum, subdepressum : capite porrecto, postice ocellis duobus instructo; oculis 

 rotundatis prominulis : prothorace ssepius transverso, anguUs posticis subrectis : scutello distincto, 

 triangulari : ehjtris pectore longioribus, angulo apicis cxteriore rotundato : alls amplis : abdomine 

 margiuato. Antenna sub fi'ontis margine laterali insertre, rectae, apicem versus incrassat^, 

 articulo primo longiusculo robusto, secundo paulo minore, ultimo subovato. Labium transversum, 

 apice sinuatum et membrana brevissima ciliata auctum. Mandibula breves mutica. Maxilla 

 bilobaj membranacex : Inbo externa apice barbato : interna extus corneo, apice denticulo termi- 

 nato, intus ciliato. Palpi maxillares articulo primo minuto, secundo longiusculo, tertio paulo 

 breviore, uUimo secundi longitudine plerumque subacuminato-fusiformi : labiates brcviusculi, 

 articulis primo et ultimo longitudine subcequalibus, secundo breviore. Mentum transversum. 

 Lif/ula biloba, lobis rotundatis ; paraglossis indistinctis. Pedes breves subtenucs {intermedii 

 plerumque approximati, scd in speeiebus Madercnsibus parum distantcs) : tibiis plus miuusve 

 subtiliter spinulosis : tarsis 5-articulatis (in nostris subtus dense pubcscentibus), articidis quatuor 

 baseos brevissimis inter se aequalibus, ultimo his conjunctis vel squali vel (ut in nostris) multo 

 longiore. 



The O media may be recognised from the members of every other genus here 

 described by the two ocelli with which the hinder region of then- forehead is fm-- 

 nished. They are insects of a more or less oblong and subdepressed form, their 

 elytra are ample (covering a larger portion of the abdomen than is the case in any 

 of the preceding groups), the terminal articulation of thou- palpi is longer than the 

 penultimate one (and more or less fusiform), theu- tibitL' are very minutely spinu- 

 lose, and their tarsi (which in the j\Iadeii-an representatives are densely pubescent 

 beneath, thus far coinciding with those of the Anthobia) have the fii-st four joints 



