of the Genus Hydroporus. 473 



I regret much that I have had at present no means of comparing 

 the two together. In the cabinets of Dr. Power, Mr. Waterhouse, 

 and the Bev. H. Clark. 



H. celatus, n. sp. 



H. oblongo-ovalis, leviter convexus, punctulatus, nitidulus, niger : capite 

 inter oculos bifoveolato, minutissime punctato, nigro, ad basin anguste 

 fermgineo : tborace lateribus obliquis subrotimdatis, marginatis, ad 

 basin transverse subdepresso et crebre punctato, antice stria transversa 

 punctorum una, plerumque haud interrupta, ad medium discum sparsim 

 punctulato vel pene impunctato : elytris ad latera subrotundatis, pune- 

 tulatis, striis duabus undique punctorum majorum a basi ad apicem : 

 antennis runs, pedibus omnino rufo-flavis. 



Long. corp. If lin., lat. f lin. 



I have before me four examples, taken at three different localities, 

 of a form of Hydroporus, which are absolutely identical in shape, 

 size, and sculpture. The form is unregistered in our British lists, 

 and I am unable to assign it to any described species known on the 

 Continent. As, in such a very difficult section of the genus as that 

 to which this species belongs, any conclusions that are not based upon 

 careful comparison of authentic types are at best but inconclusive, 

 it is only perhaps provisionally that the species will stand as H. 

 celatus. My own belief is, having carefully examined descriptions 

 and also examples of most of the species found on the Continent, that 

 it will prove to be as yetundescribed ; at all events, it is new to Great 

 Britain. In general form it closely resembles H. vittula, Er. It is 

 however, a much larger insect, the punctures on the thorax are less 

 regularly distributed (the base being deeply punctate, while the 

 medial surface is almost impunctate), the striae on the elytra are less 

 distinct (and only punctured striae, not slight longitudinal depres- 

 sions), while the legs are entirely rufo-flavous, not suffused with 

 fuscous. From H. nigrita, Fab., it may be distinguished, as well by 

 its much greater size, as by its less-coarse punctation, and by its 

 striae on the elytra : in size, and glossiness of hue, and general 

 appearance it is very near to H. melanarius, Sturm, (according to 

 examples in my cabinet) ; but it is in form more oval, not so parallel, 

 the punctures on the elytra are slightly more frequent, and in this 

 latter species there are no traces of punctate striae ; it is broader, and 

 not so long as H. Gyllenhallii, Schiodte ; it is very like a large H. 

 pubescens, Gyll., but with finer punctation and other minor differences. 

 Its position in our British cabinets should be between H. Gyllenhallii 

 and H. melanarius. Among species not hitherto detected as British, 

 it would resemble most closely H. incertus, Aube ; this species, how- 



