Hydrophilidce of New Zealand. 471 



however, succeeded in finding a good test for the sexes 

 in the shape of the claws of the front feet, which in the 

 male are much more abruptly bent than they are in the 

 female, and are furnished with a shorter but more 

 prominent lobe. 



Rygmodus modestus. 



Rygmodus modestus, White, Voy. Er. and Terr., p. 11. 

 R. pedinoides, White, op, cit., p. 12. 



Ovalis, sat convexus, nitidiis, niger, elytris vel metallescentibus 

 vel cyaneis, autennarum articulo basali sordide testaceo ; protliorace 

 in medio parce obsoleteque punctate ; elytris striatis, interstitiis ad 

 basin planis, apicem versus couvexis, sat crebre fortiter (versus 

 suturam subtilius) punctatis. Long. 6 mm. 



This is apparently the commonest and most variable 

 species, and the one that has least peculiarities. 



Auckland and Greymouth; abundant in both localities, 

 and usually represented in the older collections of New 

 Zealand Coleoptera. The Auckland individuals are 

 smaller and more brilliantly coloured than those from 

 Greymouth, but no important difference exists between 

 them. I also quite fail to find any character of im- 

 portance by which to distinguish the types of R. modestus 

 and R. ijedinoides, White, from one another, and think 

 it very probable that R. incertus, R. opimus, and R. 

 cyaneus, Broun, may also be the same species. 



Rygmodus femoratus, n. s. 



Ovalis, nitidus, niger, femoribus Isete rufo-testaceis, elytris vel 

 cyaneo-nigris vel viridi-nigris. Long. 8 mm., lat. 4^ mm. 



This species is readily distinguished by the bright- 

 coloured femora. In general aspect it is excessively 

 similar to the larger, more obscurely-coloured varieties 

 of R. modestus, and differs but little from it in details ; it 

 has, however, the punctuation on the disc of the thorax 

 less effaced, that of the interstices of the wing-cases 

 slightly more distinct, and the explanate or flattened-out 

 side of the thorax broader. It varies a good deal in the 

 punctuation, and in the convexity of the interstices ; it 

 is not a mere variety of R. modestus, as, besides the 

 evident, though slight, distinctions of sculpture and of 

 the colour of the legs, the minute pubescent punctuation 



TRANS. ENT. SOC. LOND. 1884. — PART IV. (dEC.) 2 K 



