1890.] THE YOUNG NATURALIST. 



95 



myself is only anxious to arrive at the true facts, and personally I am 

 quite content to leave the matter to the judgment of the readers of 

 this Journal. 



Greenwich, 

 April yd, 1890. 



WATER BEETLES AT BURNHAM, SOMERSET, 



By ROBERT GILLO. 



Whilst spending a few days at Burnham during the first week in 

 September, I determined to see what Water Beetles the ponds and 

 ditches would produce if persistently dragged with the net day after 

 day. I soon found that some ponds which yielded nothing worth 

 having on one occasion, on another would produce good things in 

 plenty ; so that it is never safe to conclude because nothing comes into 

 the net on the first few trials that therefore there is nothing in the 

 pond worth working for. A great deal depends upon how the net is 

 handled. It is impossible to describe the various methods, but in a 

 general way I may say that it is best to plunge the net deeply in the 

 water as gently as possible, and then to bring it up under the water 

 plants. As the result of four or five days collecting, I noticed 30 

 species of Hydradephaga, and 12 of Palpicornia, the commoner species 

 numbers. Some appeared to be partial to ponds of clear water whilst 

 others only occurred in ditches that were anything but clear or sweet. 

 The species were: — Haliplus obliquus, mucronatus, varicgatus, fluviatilis, 

 riiftcollis, lineatocollis ; Pelobius Hermanni ; Hyphydrus ovatus ; Hydroporus 

 pictus, palustris, erythrocephahis, lineatus, confluens; Noterus sparsus ; 

 Laccophilns obscurus ; Colymbetes fuscus; Lioptems riificollis; Dytiscus 

 marginalis, circnmfiexus, punctitlatus ; Agabus bipustulattis , sturmi, nebulosus; 

 Ilybius fuliginosus, ater, giittiger ; Acilus snlcatus ; Hydaticus transver- 

 saliz, Gyrinus natator, and elongatus. 



The species of Palpicornia were: — Hydrophilus piceus; Hydrobias 

 fuscipes and oblongus ; Philhydrns testacens, marinus, ovalis; Laccobins 

 sinuatus and alutaceus ; Berosus affinis; Heloplwrus aquations and brevi- 

 palpis; and Ochthebius cevatus. 



In addition to these there were many others such as Elmis, Parnus, 

 &c, which I have not included, not looking upon them as true water 

 beetles. 



