VORACITY OP LARVAE. 191 



hairy, somewhat like the caterpillar of the garden tiger-moth, 

 and is endued with a great degree of vitality, for long im- 

 mersion in water does not destroy life. Being often exposed 

 to that element, they seem provided with the power of endur- 

 ing its approaches. They feed twice in the day, ahout ten 

 o'clock in the morning, and four in the afternoon. If over- 

 taken by the tide while feeding, they mount to the top of the 

 grassland then, if obliged to relinquish their hold, contracting 

 themselves into a circular form, they commit themselves to 

 the water. By this means they are washed to the borders of 

 the marsh, where they are left by the wash of the sea in heaps, 

 but alive, and in a short time ready to recommence their de- 

 predations upon the meadows. The hair upon their bodies 

 seems to possess a repelling power, which secures the spiracles 

 from the admission or access of the water, for were the latter 

 to be the case, the insect would be drowned. Their most fa- 

 vourite food is the onion grass, which is very succulent ; but 

 they are not fastidious, and eat with avidity " fox" and " bot- 

 tom grass," and even " thatch" and " sedge." By the 1st of 

 August these caterpillars have attained their greatest size ; 

 they now become very voracious, and continue eating all the 

 day and night without intermission, by which means the hay 

 crops are greatly detrimented. Soon they leave the meadows, 

 aggregated in great numbers, and commence their wandering 

 state, or " begin to run," as is the phrase, devouring every 

 thing in their progress. Corn-fields, gardens, and even the 

 coarse and rank produce of road sides, afford them temporary 

 nourishment, until they have found a place of security against 

 the tide and weather. Another moth, belonging to the same 

 group, of whose proceedings an account was published in 

 1782, by Mr. W. Curtis, under the name of the brown-tail 

 moth, Porthesia aurif.ua, is occasionally not less numerous 

 or injurious in our own country. In the year above mention- 

 ed, so vast were their numbers, that the trees were despoiled 



