42 ON THE AGROTIS VASTATOR, 



many species which have a range nearly world-wide. The cater- 

 pillars of several species, such as the one now under consideration, 

 are very destructive, on account of their numbers, feeding on the 

 roots and leaves of low herbage, and hiding during the extreme 

 heat of noon under clods of earth, stones and other convenient 

 places. Their voracious attacks upon the growing crops in the 

 field or in the garden, have been for many years past experienced 

 to a frightful extent, and are too well known to require description. 

 The number of larvse in seasons which prove favourable for their 

 development almost surpasses belief, but our astonishment will 

 cease when we take into consideration the probable progeny 

 of those vast numbers of moths now infesting the sea-board of 

 this land for some hundred miles, each pair producing an oflF- 

 spring of many hundreds, who in their turn, before the cold sets 

 in, will prove equally prolific. The caterpillar no sooner emerges 

 from the egg than it begins the great business of life, and falls 

 vigorously to work — eating — and his growth is marvellously rapid ; 

 " few creatures can equal him in the capacity for doubling his 

 weight, not even the starved lodging-house slavey when she gets 

 to her new place, with carte-blanche allowance and the key 

 of the pantry ; for in the course of twenty-four hours, he will 

 have consumed more than twice his own weight of food ; and 

 with such persevering avidity does he ply his pleasant task, that, 

 it is stated, a caterpillar in the course of one month, has increased 

 nearly ten thousand times his original weight on leaving the egg ; 

 and to furnish this increase of substance, has consumed the pro- 

 digious quantity of forty thousand times his weight of food — 

 truly a ruinous rate of living !" ' A few years ago on the Hunter 

 River, I carefully examined a paddock of twenty-five acres, under 

 oats for hay, which was much infested by the caterpillars of this 

 species, and found that nearly every stalk had at least one cater- 

 pillar on it, numbers had two ; many three : taking the plants at 

 twenty to the square foot, and each with only one caterpillar, the 

 result would be 21,780,000 of these insects, and supposing that 

 all these lived to become moths, each pair producing by the end 

 of the season a progeny of 80,000,^ the total produce for the 



J British Butterliies, by W. S. Coleman, 1860. 

 '^- Reaumur. 



