THE BOMBYCINA. II5 



three darkish bands, give it a very quiet appearance. It appears 

 in the woods about the months of August and September. The 

 lemales lay their eggs in masses upon the trunks or larger 

 branches of oak trees, and cover them with the hairs from the 

 body. The caterpillars are hatched in the month of May, 

 and are collected in families which contain hundreds of mem- 

 bers. They form an irregular web, in which they remain very 

 quietly during the daytime, but in the evening they crawl upon 

 the foliage and eat voraciously. When they have finished their 

 meal they either return to their old home or make another. 

 One of these nests may cover a considerable part of the trunk of 

 a tree, and it consists of several layers of web, one over the 

 other, but very intimately woven together. Every observer must 

 be struck with the manifest order and routine observed by these 

 caterpillars in their peregrinations. If the nests are examined 

 during the daytime all is quiet within, and the caterpillars 

 are crowded one upon the other, and are almost motionless. 

 As soon, however, as the sun has gone down there is a slight 

 movement, and then a general waking up. A caterpillar leaves 

 the nest, and commences climbing the trunk. It is followed by 

 another, and this one by a third, and then comes a rank of three 

 or four individuals, which is followed by one of many more, and 

 so on. 



The ranks go on increasing in their numbers in a very regular 

 manner, but the column at last becomes confused. There may 

 be two or three caterpillars instead of one in the second and 

 third ranks, but one larva invariably leads the array in its curious 

 procession. After feasting, the same order is taken up, and the 

 host of caterpillars returns to camp in the same formation. Even 

 if they move from one branch to another this procession is wit- 

 nessed, and yet nothing distinguishes the leader from the others, so 

 that the instinct which admits of these manoeuvres is very remark- 

 able. When the larvae have attained their full growth they gra- 

 dually increase the strength of the walls of their nest with their 

 moulted skins, and then each one makes its cocoon inside and be- 

 comes transformed. In the engraving, which represents a scene in 

 the Bois de Boulogne, near Paris, the processional caterpillars are 

 on the march and are being attacked by a large beetle and its 



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