The Natural History of Selborne

The oestrus curvicauda is found in Lancashire: probably the kingdom over.  It lays it’s nits on horses legs, flanks, &c. each one on a single hair.  The maggots when hatched do not enter the horses skins, but fall to the ground.  On what & how are they supported?  * Earthworms obtain & encrease in the grass-walks, where in levelling they were dug down more than 18 inches.   So that they were either left in the soil, deep as it was removed: or else the eggs or young remained in the turf.  Worms seem to eat the earth;   also brick-dust lying among the earth, as appears by their casts.   They delight in slopes, probably to avoid being flooded, & perhaps supply slopes with mould, as it is washed away by rains.  They draw straws, stalks of vine-leaves, &c. into their holes, no doubt for the purpose of food.  Without worms perhaps vegetation would go on but lamely, since they perforate, loosen, & meliorate the soil, rendering it pervious to rains, the fibres of plants, & c.  Worms come out all the winter in mild seasons.