CAtALOGITE OF MOTHS. 41 



"Wailes says of this species, "rarely met with, hut prohahly 

 more abundant than supposed, if sought for on the sea-coa3t, 

 where the food of the larva, Galium verum, abounds. Twizell, 

 twice— P. J. Selby, Esq. ; Embleton — Robert Embleton, Esq." 

 Since 1857, when that was written, we have learnt much more 

 of the life-history of this species. It was known that when the 

 larvae were found at large, though it was not difficult to get 

 them to pupate, the imago rarely emerged. The late Mr. "W. H. 

 Tugwell, of Greenwich, reared a larger number of this species 

 than perhaps any other British Entomologist. This he accom- 

 plished by "forcing" the pupae in the autumn. He found that 

 the imagines so produced were always smaller than captured 

 specimens, and arrived at the conclusion, which has been gene- 

 rally accepted, that D. Galii, when found as a perfect insect is 

 an immigrant, and when as a larva it is the progeny of an immi- 

 grant. That if fed up on our sandy shores, though it may, and 

 probably often does pupate, it lacks strength to survive the 

 winter, and, notwithstanding its abundance one year, it is seen 

 no more until there is another immigration. It is a species 

 which appears occasionally to migrate in large numbers, and it 

 has happened, as in 1859, 1870, and 1888, that it has spread 

 over the entire island, and been found in one stage or another 

 in almost all parts of the kingdom. A single larva was taken 

 at Hartlepool by AEr. Appleton in 1859. It pupated, but the 

 imago did not emerge. Another was taken by Mr. Christopher 

 Eales at South Shields on 24th Sept., 1861. This pupated, and 

 the perfect insect appeared 18th July, 1862 (see iNat. Hist. 

 Trans., vol. v., p. 285). An imago was taken at rest in a ship- 

 yard at Hartlepool in 1870 by Mr. Ritchie and given to me. 

 Another was found on the dock side 19th August, 1888, and 

 given to Mr. Gardner, and a third was brought to me the next 

 day. These tbree specimens were all in beautiful condition and 

 it was difficult to believe they had travelled far. In the autumn 

 of that year Mr. Gardner found two larvae on the sand-hills to 

 the north of Hartlepool, but he failed to rear the perfect insect. 



