SHARP: HYDRADEPHAGA OF LANCASHIRE AND CHESHIRE. 203 
at Leasowe. The last genus which I have to mention is Ovechtochilus 
(with stretched lip or edge). There is one species which occurs in 
the Bollin, also the Alyn, and doubtless many other streams. 
Such then is a brief résumé of the records of the members of the 
group Hydradephaga which our district has so far supplied, about 
seventy-four species out of a total of one hundred and twenty-nine ; 
and of twenty-four genera, there are but four of which we have no 
representative. 
It is chiefly in the denizens of clear running waters that we are 
deficient, but the immediate vicinity of Liverpool is not noted for 
its clear brooks and shingly streamlets. Then there are some species 
purely local like Hydrovatus clypealis from Portsmouth, and Bedissus 
minutissumus only taken in Devonshire ; there are also a few northern 
and semi-arctic species which we could not expect to find, such as 
Dytiscus lapponicus, Agabus arcticus,and others. Then there are 
a few forms which seem restricted to a southern range. ut on 
the whole we have as large a proportion of the total numbers of the 
group as perhaps any other district of an equal size can boast of. 
We are fortunate in possessing singular facilities for working these 
insects in the number of pits or ponds which stud the surface of all 
South Lancashire and West Cheshire. All over that great belt. of 
glacial clay, which like a thick veil covers the Triassic sandstones, 
these quiet ponds mark nearly every field. To account for their 
origin we must go back to the years long past, when wheat was the 
Staple crop of the heavy clay lands, and not, as now, restricted to an 
isolated field here and there. Then, when patent manures were 
unknown, the only way of recuperating the surface, exhausted as it must 
have been then by a long course of wheat crops, was by application of 
the virgin sub-soil as a top-dressing. For that purpose were dug those 
deep pits, and there they have remained ever since, the home of 
generations of water-beetles. Usually dug in the corners of the fields, 
great oaks have grown up around them, and tangles of gorse and 
hawthorn shut them in. There the sly Water-Hen paddles silently out 
from the thick reed beds, and into their still waters on winter evenings 
the wheeling wild ducks drop with a splash that resounds all across the 
pastures. It is these pools that make the study of the Hydradephaga so 
fascinating. No inverting tons of angular stones on bleak mountain 
Sides, no grubbing among dung and carrion. Here is all the charm 
of trout-fishing, the bright April morning—for April is the best 
month for the Hydradephaga, before the water-weeds have grown 
too much—the -yellow gorse, the catkined sallows. You may have 
the luck to see a kingfisher, a resplendent vision of sapphire, for 
a moment he sits poised on an aspen bough, then like a flash he has 
July 1892. 
