1890.] 



THE YOUNG NATURALIST. 



163 



1888 were immigrants, but not their larva." Did any one really go so 

 far as to accuse Mr. Tutt of believing that larva were immigrants. 

 Certainly I never did, the point at issue is the origin of the imagines 

 of 1888. Mr. Tutt says these were immigrants, but whence ? It is 

 here that the theory is so very vague. These swarms must have had 

 some mundane origin. Galii must have a metopolis somewhere. Can 

 it not even be approximately fixed ? Is it the littoral of the low 

 Countries ? Is it the interior of Europe, of Africa, or the moon ? 

 The species must have been in no small numbers somewhere, when 

 in the early summer of 1888 they issued from their mysterious home. 

 Their hosts impinged on the English coast from Dungeness to 

 Aberdeen, they crossed England, were in force on the Cheshire coast, 

 and even crossed the Irish Sea. But let us for a moment consider 

 this Cheshire case, because as I tried to show in my second paper, if 

 the immigration theory will not fit Wallasey, it is no use its fitting 

 Deal. At Wallasey we have a narrow strip of coast sandhills, some 

 two miles long. At the very lowest computation 200 imagines must 

 have reached that spot in order to explain the abundance of their 

 progeny as larvae. What incalculable myriads then, must have 

 originally started, in order that that strip of coast in the West of Eng- 

 land, some two miles long, and perhaps 600 miles from the point of 

 origin, should have intercepted 200 of them. No doubt Mr. Tutt 

 will refer me to the notorious flights of Cardui in 1879 as a parallel, 

 but I would reply that those myriads were traceable as they travelled. 

 Europe was alive with Cardui. The alpine snows were discoloured 

 with their innumerable corpses ; they invaded towns, they were seen 

 far out at sea, and our Southern coasts for miles were strewn with 

 the wreck of their armies. Does this phenomenon afford any 

 parallel to the case of Galii ? Who ever saw one single specimen 

 of that insect except close to its natural habitat ? Was there 

 ever a recorded case of one alighting on any ship ? Were they 

 indeed observed in any spot in all Europe during that summer of 

 1888, in greater abundance than usual, except \ in these islands. 

 A few were caught during June and July in England ; were they 

 worn and battered by their long flight from the remote cradle of their 

 race ? Let those Entomologists who captured them announce." In 

 * The specimen that reached my hands in June, 1888, was very fine and perfect. 

 I may add that though insects caught on shipboard are continually brought to me by 

 seafaring friends, Galii has never been among them, though I have more than once 

 had once had Lineata. — J. E. Robson. 



