24 ADEPHAGA. 
the wing-cases. The specimens before me show no sexual differences, and have the 
tarsi slender. 
13. Bidessus abjectus. 
Breviter ovalis, fuscus, limbo dilutiore, antennarum basi testacea, pedibus fusco-testaceis; prothorace parce 
punctato, striga profunde impressa; elytris sat crebre fortiter punctatis, striga basali breviuscula ; coxis 
posticis abdominisque basi punctis paucis magnis. 
s nitidus, corpore supra conspicue punctato. 
2 opaca, corpore supra fere impunctato. 
Long. 3, lat. 4 lin. 
Hab. Muxico, Oaxaca (Hoge). 
This species is allied to Hydroporus fuscatus, Crotch, but is of a very much shorter 
form and of more obscure colour, the elytra being without markings; and the difference 
of the sexes is remarkable. From all the varieties of Hydroporus affinis, Say, it may be 
distinguished by the presence of coarse punctures on the cox ; it is also shorter in form 
than the common species. 
14. Bidessus magensis. 
Hydroporus magensis, Clk. Ann. & Mag. Nat. Hist. ser. 3, x. p. 182°. 
Hab. Mexico 1. 
15. Bidessus spretus. 
Breviter ovalis, nitidus, fere sine pubescentia, testaceus, capite elytrisque infuscatis, antennis versus apicem 
fusco-testaceis, abdomine pectoreque nigricantibus; elytris tantum sparsim obsoleteque punctatis, stria 
suturali profunda, basi plica conspicua sat elongata. 
Long. 3, lat. vix 2 lin. 
Hab. Guatemaa, San Geronimo, Paso Antonio, 400 feet (Champion). 
This species is very similar to Hydroporus lacustris, from which, however, it can be 
distinguished at once by possessing a deep distinct sutural stria ; the wing-cases, too, are 
more shining, their punctuation being more scanty. The basal stria or plica is longer 
than that of the thorax, as is the case in H. lacustris. All the specimens before me 
have the tarsi slender; and I can see no sexual distinctions. 
16. Bidessus obtusus. 
Oblongo-ovalis, postice minus acuminatus, sine pubescentia, nitidus, testaceus; elytris lineis latiusculis 
elongatis nigris, versus suturam sparsim punctatis, impressione basali parum elongata; corpore subtus 
fere impunctato. 
15 ]j 
Long. 1, lat. $—3 lin. 
Hab. GuatEMALA, Paso Antonio, 400 feet (Champion). 
Antenne short and rather stout, clear yellow. Head impunctate. Thorax impunctate, 
but on each side with a deep and rather broad basal impression. Elytra distinctly 
