4!2 On Aquatic Cariticoivus Culeoptera or VytiscidoB. 



In the male the front and middle tarsi are rather elongate and moderately broad, 

 the front ones furnished with a single abruptly curved claw, which bears a tooth 

 at the base ; the hind femora are dilated towards the extremity and furnished with 

 a sharp hooked tooth. In the female the front tarsi are very slender and com- 

 })ressed, the second and third joints showing a well marked constriction, or neck, 

 at the base. 



Australia. 427. ' . 



434, Hydroporus blakei, Clk,, M.C. — Oblongo-ovalis, latiusculus, brevissirao 

 pubescens, densius subtiliter punctatus, opacus, ferruginous ; elytris fuscis, signa- 

 turis externis lineaque suturali vage ferrugineis ; prothorace basi sequali ; elytris 

 apicibus subprolongatis, sinuatim truncatis ; corpore subtus densius punctato, opaco, 

 coxis posterioribus interne fortius punctatis. Long. 4s, lat. 2-J m.m. 



In the male the front and middle tarsi are a good deal dilated, the third joint is 

 divided nearly to the base so that the lobes are elongate and slender ; on the front 

 feet there is a single unguiculu3, which is short, thick, and sinuate, and has a sharp 

 tooth at the base ; the intermediate tibias are curved and incrassate, and bear a 

 large angular projection on the middle externally. 



Austi-alia and Tasmania. 428. 



435. AntijDorus curtulus, n. sp. — Latus, brevis, omnium brevissime pubescens, 

 densissime subtiliter punctatus, opacus, testaceus, prothorace anterius et posterius 

 infuscato, elytris nigro-fuscis, sutura, margine externo signaturisque versus latera 

 testaceis ; elytris apicibus sub-prolongatis, emarginato-truncatis ; corpore subtus 

 densissime subtilis.sinie punctato, opaco. Long. 3s, lat. vix 2 m.m. 



I have seen only females, which are very similar to that sex of Hydroporus 

 blakei, but the species is readily distinguished by the smaller size and shorter and 

 broader form, the distinct markings of the elytra, and the rather finer and denser 

 punctuation of the under surface. 



It is possible that this species may prove to be the Hydroporus bakewelli, Clk. 



Australia, (Sidney). 429. 



I. 3 S.— Genus XECTEROSOMA. 



The true fourth joint of the front tarsus is conspicuously exposed at the base 

 of the terminal joint. This character is more conspicuous in the males than in the 

 females, and is frequently accompanied by a great elongation of the terminal 



