51 4- LOCAL DISTRIBUTION OF INSECTS. 
drachna, Eyla'is and Limnochares are purely aquatic. 
Several spiders will walk over the water ; and one species 
(Argyroncta aquatica) inhabits it a . The stagnant waters 
in your vicinity will produce different species from run- 
ning ones. Thus Hallplus elevatus, &c. inhabits only the 
latter, while the majority of the DytiscidcB abound most 
in the former : the more minute ones may be sought for 
with success amongst the duckweed that covers a pool. 
I do not recollect rinding any insect in waters absolutely 
salt b ; but brackish waters produce peculiar species : in 
these only, Hydrcena marina occurs ; and many of those 
large-eyed Cimicidce{Acanthia) i as A. saltatoria, littoralis, 
and Zosterce occur in places where salt water has been. 
Latreille observes, that the genus Pimelia is to be met 
with only where the soil is impregnated with saline par- 
ticles, or where the species of the genus Salsola abound c . 
Heaths, though they do not afford numerous insects, 
have their rarities. Cicindela sylvatica, Carabus nitens 
and arvensis, frequent them, and are not elsewhere to be 
seen. Curculio nehdosus is also to be found on them, in 
places where the turf has been peeled ; and some scarce 
Lepidoptcra. In their vicinity, in sunny sandy banks, 
some of the rarer Ammophilce and Pompili may be taken; 
and it is here only that I have ever met with Panurgns d . 
Meadows and pastures are not to be neglected. Early 
in the year, when they are yellow with the blossoms of 
Ranunculus bidbosus, Leontodon Taraxacum, &c, many 
a See Vol. I. p. 470—. 
b A species of Gyrinus (G. Viola aquatica), described by Modeer 
(Linn. Syst. Nat. Ed. Gmel. i. 1612. n. 9.), is said to inhabit salt 
water. 
c Geograph. &c. 6. d Apis*, a. Mon. Ap. Angl. ii. 178 — . 
