RAVAGES OF CATERPILLARS. 211 



cages ; but, contrary to the experiment just quoted, 

 all of these were hatched during the same autumn.* 

 The difference of temperature and moisture in par- 

 ticular seasons may produce this diversity. 



An alarm, similar to those we have recorded, was 

 produced in France in 1735 by the green striped 

 caterpillars of a moth very common in Britain, called 

 by collectors, from a mark on its upper wings, the Y, or 

 more properly the y moth (Plusia Gamma, OCHS.). 

 Though ranked in some classifications amongst the 

 nocturnal moths, it flies chiefly by day, and may be seen 

 in Battersea-fields, or other moist meadows, flitting 

 from herb to herb and flower to flower, in short and 

 low flights; for it seldom soars higher than the tallest 

 grass-stem, or the crimson flower-heads of the knap- 

 weed, upon whose honey it sometimes regales, re- 

 maining on the wing all the while it is sipping it. 

 During the cold rainy summer of 1829 it was almost 

 the only moth which appeared plentiful. "j* At least 

 two broods seem to be produced during the season ; 

 which may account for its being found from May till 

 the setting-in of the winter frosts. 



Notwithstanding it being so plentiful, however, we 

 have not heard of its having ever been so destruc- 

 tive here as in France, were, as usual, the most 

 improbable causes were assigned for its increase. 

 * In some places,' says Reaumur, c they assured me 

 they had seen an old soldier throw the spell ; and in 

 other places an ugly and mischievous old woman had 

 wrought all the evil.'J These supposed supernatu- 

 ral agents, however, must have been either very nu- 

 merous or very active to fill, not only the gardens, 

 but every field, with legions of those caterpillars, which 

 devoured almost every green thing, and left only the 

 stalks as monuments of their devastation. The 

 alarm proceeded farther, for it began to be whispered 



* J. R. t J. R. $ Reaumur, ii, 336. 



