814 AUSTRALIAN COLEOPTERA, WITH DESCRIPTIONS OF NEW SPECIES, 



The basal joint of the maxillary palpi is testaceous, the 2nd 

 and 3rd nearly black, with the extreme apices paler, the 4th 

 reddish pitchy ; the anterior tarsi are reddish pitchy. Apart from 

 generic characters, size and color, this insect is so extremely similar 

 to Hi/drobiomorpJia Tepperi that the descri[^tion of that species will 

 suffice for it, subject to the following remarks : — the prothorax 

 is evenly emarginate in front, without any bisinuation ; the 

 ) junctures forming the series on the head, prothorax, and elytra are 

 evidently finer ; and the elytral series are not so regular, the inner 

 four appearing to consist each of two closely adjacent rows 

 confused together, while the series close to the lateral margin is 

 wanting. The general form also is less elongate. 



Probably this insect is allied to iS*. nitidulus, Macl., the description 

 of which is rather brief ; but that species is said to have the palpi 

 reil and to have "faint traces of a few rows of punctures on the 

 elytra." In S. tenebricosus the rows are perfectly well-defined and 

 conspicuous.* 



A single example taken near Palmerston, N.T., by Mr. J. P. 

 Tepper. 



Hydrobiomorpha, gen.nov. (Hydrophilid.e). 



Mentum antice leviter rotundatum hand sinuatum, angulis 

 anticis vix emarginatis. 



Mandibula apice bilobata. 



* Since writing the above I have found in the South Australian Museum 

 a specimen (in wretched condition) which is probably S. nitidulus, Macl. 

 It is extremely like S. tenebricosus, but differs in having the maxillary palpi 

 red, and the sculpture of the elytra faint and running more regularly in 

 single rows. The sternal spine also differs ; in both species it reaches nearly 

 to the apex of the first ventral segment and is pointed behind, but in 

 tembricosxir'i the point forms the apex of the lower edge of the spine (i.e., that 

 nearest to the surface of the body), so that the upper outline of the carina 

 viewed from the side is declivous at the extrem<i apex ; while in the other 

 species this is reversed and the point forms the apex of the upper edge of the 

 spine, so that the upper outline of the carina viewed from the side is 

 straight to the apex. 



