(luring llie extreme beat of noon under clods of earth, stones, and other convenient 

 places. The number of larva?, in seasons which prove favourable for their development, 

 almost surpasses belief. .... A few years ago, on the Hunter River, I carefully 

 examined a paddock of twenty-live acres, under oats for bay, which was much infested 

 by the caterpillars of this species, and found that nearly every stalk had at least one 

 caterpillar on it; numbers bad two, many three. Taking the plants at twenty lo 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 ihe season a progeny of 80,000, the total produce for the twenty- five acres 

 would amount to 871.200,000,000. What, then, calculating under the same condi- 

 tions, would be the nnmlter of the caterpillars which were at the time I allude to 

 ravaging whole districts? A bmg line of figures almost unpronounceable. 



" Allowing for every reasonable loss caused by weather not unusually severe, 

 accident, or their numerous enemies, still there would remain quite sufficient to produce 

 those vast numbers of moths, collected together from a wide range of country, and 

 seen clustering in caves, under ledges of rocks, in churches, houses, barns, in every 

 nook and cranny where their gregarious habits lead them, seeking shelter from the 

 glare of day. I therefore think that this natural increase, aided by favourable 

 weather, is quite sufficient to account for the swarms of moths recently seen in many 

 localities, without having recourse to improbable theories. All moths are, in their 

 primary stages, purely terrestrial, and cannot 'come in from the sea.' They cannot 

 be born there, neither are their wings adapted for so long a flight as lo cross the ocean 

 from any point of land to the eastward of our coast, particularly ' in the teeth of 

 westerly winds.' Indeed, many swarms of insects, besides the Lepidoptera, are known 

 to he blown from the land, while a few others wilfully fly seaward under some 

 unaccountable, almost insane, desire; but all these inevitably perish. I would suggest 

 that the moths seen by vessels at sea were either endeavouring vainly to emigrate, or, 

 what is far more probable, were driven away from the land by the prevalent westerly 

 winds, and perished by thousands in the ocean ; those seen returning to the shore were 

 the fortunate few that had escaped before being carried too far lo sea. I remember, 

 some years ago, walking along the sands for about five miles between Newcastle and 

 Redhead, and I observed an almost continuous undulating line of dead bodies, several 

 deep, of these moths, marking the wash of high water along the whole of this length of 

 beach, interrupted only by the rocky headlands; and probably this exhibition of the 

 fate of these insects in such vast numbers was continued for a considerable distance 

 on either han'd. 



" Were it not for the wholesale destruction of these vast assemblages of insect 

 pests, caused by the violence of winds — by the fall of rain for several days successively 

 — by sudden changes of teinperature — and by the host of enemies, following in their 

 vviike, consisting of insectivorous birds and reptiles, and the numerous family of the 

 Ichneumonidae, I fear all the endeavours of man by artificial means to eradicate them 

 would be baffled. The abundant food furnished by the roots and leaves of the various 

 weeds and grasses growing over a vast extent of waste lands, will always ensure too 

 ample a supply of such noxious creatures. We can, however, check in some degree 

 the injury to our crops, and thus moderate the evil, by ploughing and harrowing the 

 fallow lands, thus cutting off" the immediate supply of food, — by passing the roller 

 again and again over the growing t;rops wheu practicable, — and by encouraging, not 



