STENUS. 657 
the elytra rather shorter, and the legs longer. I have little doubt it is a distinct 
Species, though only one female example has been obtained. 
40. Stenus ambulator. 
Nigerrimus, nitidus, fortiter punctatus; antennarum, palporum, femorum tibiarumque basibus testaceis ; 
capite bisulcato, vertice in medio latius sat argute elevato et polito; prothorace brevi, basi subconstricto, 
fortiter punctato, medio area levigata parum discreta. 
Long. 4 millim. 
Hab. Guatemata, Cubilguitz, San Gerénimo, Duefias (Champion). 
Very similar to S. micans ; but the pubescence of the anterior parts almost wanting, 
the head considerably broader and with the smooth elevation on the middle of the vertex 
wider, the elytral punctuation more scanty, and the male characters very different. 
The head is about as broad as the elytra. The thorax is short, only about as long as 
broad, strongly rounded at the sides, closely but unequally punctate. Elytra coarsely 
but rather sparingly punctate. Tibie fusco-testaceous, paler at the knee, but without 
definite annulation there. Male with a broad very short excision of the last ventral 
plate ; the preceding segment nearly simple, but feebly deplanate, and with the hind 
margin just perceptibly emarginate. 
Four examples. The description is made from the two found at Duefas; the other 
two are females, and differ slightly. 
41. Stenus gentilis. (Tab. XVII. fig. 11.) 
Gracilior, nigerrimus, nitidus, tenuissime pubescens ; antennis, palpis pedibusque rufo-testaceis, illis extrorsum 
femorumque apicibus fuscis; vertice plaga elevata, lata et arguta; prothorace fere subcylindrico, irregu- 
lariter punctato; elytris parce punctatis. 
Long. 4 millim. 
Hab. Guatemata, Cubilguitz 1000 feet (Champion). 
Palpi testaceous, the terminal joint rather more sordid. Head only moderately broad, 
the elevation on the vertex very distinct and wide. Thorax rather narrow, gently 
rounded at the sides, rather uneven, coarsely and irregularly punctate, with a space on 
the middle impunctate. Elytra longer than the thorax, rather closely and coarsely 
punctate, a little rugose on a slightly depressed space behind the shoulders. Hind 
body rather slender, feebly punctate, terminated by two distinct slender sete. Legs 
rather long; yellowish-red, the tips of the femora darker, the tibize more or less slightly 
infuscate. Male with a very broad moderately deep excision of the last ventral plate ; 
the preceding segment with the pubescence projecting backwards in the middle behind 
the margin. Six examples. 
This insect is easily distinguished, though to a considerable extent intermediate 
between iS. ambulator and SS. salvint. The thorax is much more cylindric than in the 
former, and the legs are different in coloration from either of the two species men- 
tioned. 
BIOL. CENTR.-AMER., Coleopt., Vol. I. Pt. 2, December 1886. 4 PP 
