APPENDIX. 
147 
been observed on the beach washed up by the tide, it has been 
a received opinion among the farmers that they are not natives 
of this country, but come across the ocean, and observations 
this year greatly corroborate the idea. Fishermen upon the 
eastern coast declare that they actually saw them arrive in 
cloud-like flights ; and from the testimony of many, it seems to 
be an indisputable fact, that they first made their appearance 
on the eastern coast; and moreover, that on their being first 
observed, they lay upon and near the cliffs so thick and so lan- 
guid that they might have been collected into heaps, lying, it is 
said, in some places two inches thick. From thence they pro- 
ceeded into the country, and even at the distance of three or 
four miles firom the coast, they were seen in multitudes, resem- 
bling swarms of bees. About ten days after the appearance of 
the flies, the young caterpillars were first observed on the under 
side of the leaves of the turnip, and in seven or eight days more 
the entire plants, except the stronger fibres, were eaten up. 
A border under the hedge was regularly spared until the body 
of the inclosure was finished ; but this done, the border was 
soon stripped, and the gateway, and even the roads have been 
seen covered with caterpillars, travelling in quest of a fresh sup- 
ply of turnips ; for the grasses, and indeed every plant, except 
the turnip and the charlock (Sinapis arvensis), they entirely 
neglect, and even die at their roots, without attempting to feed 
upon them. This destruction has not been confined within a 
few miles of the eastern coast, but has reached more or less 
into the very centre of the county. The mischief, however, in 
the western parts of Norfolk, and even on the north coast, has 
been less general, but I am afraid it may be said, with a great 
deal of truth, that one half of the turnips in the county have 
been cut off by this voracious animal. 
A circumstance so discouraging to industry and injurious to 
the public at large, will, I flatter myself, be thought a suflicient 
apology for troubling you with a relation of it, and for my tak- 
ing the liberty of sending you a male and female fly, also one of 
the animals in its caterpillar, and one which is in its chrysalis 
state, for your inspection, hoping that the public may become 
