l56 TURNIP. 



Here Mr. Robson gave me long details as to what kinds of plants 

 grew in the neighbourhood (where there were any at all), and of amount 

 of town land, showing that it was absolutely impossible that the moths 

 should have been bred where they appeared. 



The moths, Mr. Robson observed, appeared on June 24th, and did 

 not increase in numbers, but in unsuitable places, such as Hartlepool, 

 they disappeared in two or three days, whilst further away a very 

 small number remained on the coast-edge, but they gradually spread 

 inland. 



In his published letter Mr. Robson shows something of rate of pro- 

 gress by mentioning that on the day of appearance at Hartlepool he 

 found none at Hezleden Dene, about one and a half miles from the 

 coast, and on June 26th they were swarming at this locality, having 

 penetrated thus far in two days. 



Mr. Robson also brought forward the further considerations : "(1) 

 For a long time previous to June 24th easterly winds prevailed, which 

 would greatly assist the moths in crossing the sea. (2) The impossi- 

 bility of so large a number of the insects passing through the larval 

 stage without being observed by either farmers, gardeners, or entomo- 

 logists. (B) Their appearance in such abundance in places like 

 Hartlepool, where there is no food at all for the larvfe. (4) The fact 

 that their ravages were confined to the sea-coast or to a restricted dis- 

 tance therefrom. (5) The fact that on June 24th the species appeared 

 simultaneously in many places." 



Mr. J. Burdon Sanderson, of Waren, Belford, about two miles from 

 the coast of Northumberland, wrote me as follows : " My own opinion 

 is that the moth came from abroad somehow or other, as the easterly 

 winds were blowing steadily for some weeks, and the attack seemed to be 

 along the coast and up the Tweed. Whether this is possible or not, 

 I do not know. My brother-in-law at Chatton, seven miles inland 

 from "Waren, saw an immense quantity of dead moths along the road 

 extending for some half-mile, evidently killed by a heavy shower which 

 had just fallen. This happened just before the attack was noticed, 

 and nothing was thought of what was to follow. Since writing the 

 above, I have just heard that on the night of July 9th an immense 

 cloud of Diamond-back Moths alighted on the Longstone, the farthest 

 of the Fames, some five miles out to sea ; this is on perfectly reliable 

 authority, and seems to favour the theory that they come from 

 abroad." 



This appearance of Diamond-back is confirmed by published infor- 

 mation from Mr. H. A. Paynter, Solicitor, Alnwick, who mentioned 

 that, being requested by Lord Walsingham to try to get him some 

 moths, he, Mr. Paynter, proceeded on July 10th to the Longstone 

 Lighthouse on the Fame Islands, where he found the rocks close to 



