On Aquatic Carnivorous Coleoptera or Dytiscidce. 603 



compressed, and furnished beneath with rather long hairs and rows of distinct 

 jialettes, 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 strige 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. 



914. 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 Isevigato, elytris punctis seriatis con- 

 spicuis, ad apiceni conspicue oblique truncatis, angulo externo dentato, acuminato. 

 Long. 11, lat. 5j 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, elongate, 

 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 joints 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 iiTegulariy strigose. The other sex is unknown to me. 



Chili. 865. 



i)15. Colymbetes nigriceps, Er., Rhantus nigriceps, M.G. — 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. ROV. DUB. SOC, N.S., VUL. II. i I 



