312 



THE GYPSY MOTH. 



1893, and repeated by Mr. Kirkland in 1894. Many obser- 

 vations had been made by different members of the force, 

 but none were so extensive or complete as those made by 

 these gentlemen, yet all agreed more or less in regard to 

 the habits. To enable one to make observations on cater- 

 pillars, on trees in the field or forest, it was necessary to 

 have some system of marking ; and for this purpose water- 

 colors were found to be excellent, and in no way injured the 

 insects ; though, in tne case of caterpillars which were to be 

 continuously observed during the entire larval stage, it was, 

 of course, necessary to reapply the color after each molt. 

 Several different colors were used, especially those which 

 contrasted strongly with the ground color of the caterpil- 

 lars. 



From these observations it appears that the caterpillars 

 remain on the egg-cluster, after hatching, from one to five 

 or more days, according to the weather, when they wander 

 off to the leaves and commence feeding. The first food 

 is the leaf hairs, and, unless one observes very carefully, 

 he might suppose that they do not feed until they are four 

 or five days old ; from this time on, however, one can see 

 where they have eaten the tissues, making small holes 

 through the leaf, though occasionally they eat from the 

 edge ; but they are extremely irregular in their manner of 

 feeding. Between the third and fourth molts their method 

 of feeding is about equally divided between eating holes 

 through the leaf and eating along the edge (Plates 40 and 

 44). From the fourth molt till they are ready to pupate, 

 they eat almost entireW from the edge of the leaf, though 

 there are occasional exceptions to this. 



Mr. Kirkland's observations on full-grown caterpillars 

 were made on the nights of July 7, 8 and 9, 1894. A me- 

 dium-sized infested elm tree was selected, and aU small twigs 

 and branches that might interfere w- ere removed. A band of 

 burlap had been put around the tmnk, about four feet fi'om 

 the ground. Twenty caterpillars, some partly and some 

 fully grown, were under the burlap. Eight of these cater- 

 pillars were marked with water-colors, in such a manner that 

 they could be distinguished from each other as well as from 

 those not marked. The caterpillars were numbered, and 



