On Aquatic Carnivorous Coleoptera or Dytiscide. 603 
compressed, and furnished beneath with rather long hairs and rows of distinct 
palettes, their claws are rather long and unequal, the anterior one being very 
slender, while the posterior is stouter, and thickened from the apex to the base and 
near the base has a sharp projecting tooth; the middle tarsi are incrassate and 
strongly compressed, and furnished beneath with long hairs and palettes ; the apical 
ventral segment in this sex is deeply strigose on its apical portion, while in the 
female these strize are quite obsolete; there is also a very slight sexual difference 
in the sculpture of the elytra, the female being slightly less shining, and having 
the sculpture near the shoulders forming more or less distinct, obliquely transverse, 
elongated scratches. 
The New Zealand specimens are smaller and more slender than those from Australia 
and Tasmania, and have the black stripes of the elytra not quite so broad and less 
coalesced at the apex, and the female sculpture more distinct; as the Australian 
specimens however show in various degrees an approach to all these points, it 
seems to me they, form but one species. 
Australia, Tasmania, New Zealand. 864. 
9i4. Lancetes unguicularis, n. sp.—Ovalis, elongatus, sat angustus, testaceus, 
pectore,abdomine, et capitis vertice nigricantibus, thorace in medio fusco-bimaculato, 
elytris nigro-reticulatis ; corpore supra fere levigato, elytris punctis seriatis con- 
spicuis, ad apicem conspicue oblique truncatis, angulo externo dentato, acuminato. 
Long. 11, lat. 53 m.m. 
The male has the basal joints of the front tarsi much incrassate and strongly 
compressed, and furnished beneath with rather long hairs, and with palettes ; their 
claws show an unequalled amount of disparity, the front one being slender, elonzate, 
and nearly straight, while the posterior is enormously developed, it is about twice 
as long as the front one, and is extremely incrassate in the vertical direction its 
upper edge being much arched, its external terminal portion is however elongate 
and slender and very acuminate; the middle tarsi have their basal jomts much 
incrassate and greatly compressed, and furnished beneath with elongate hairs, and 
with palettes, their fifth joint is elongate and its claws are slender, elongate and 
equal ; the last ventral segment is so cut away on each side, that its middle portion 
forms a projecting lobe; this segment towards its apex is closely, but rather finely 
and irregularly strigose. The other sex is unknown to me. 
Chili, 865, 
915. Colymbetes nigriceps, Er., Rhantus ngriceps, M.C.—Ovalis, sat elongatus, 
vix angustus, niger, antennis testaceis articulis 5-11 extrorsum plus minusve 
infuscatis, thorace elytrisque testaceis, illo medio fascia transversa nigra, his nigro- 
TRANS. ROY. DUB. SOC., N.S., VOL. IJ, 41 
