310 



THE GYPSY MOTH. 



the caterpillar raises its head and swings it from side to side, 

 resting at intervals, and begins feeding in about twenty-four 

 hours. The increase in the size of the body over that of the 

 preceding molt, is more plainly noticed after the caterpillar 

 has taken its first meal, but the increased size of the head is 

 apparent at once. When first emerged from the molted skin 

 the head is nearly cream- white, with faint darker markings, 

 and all the colors of the body are light, but after a few 

 hours they darken to the normal shades. The dorsal retrac- 

 tile tubercles are very prominent immediately after molting, 

 but regain their normal size in a short time. 



Caterpillars attracted to Light. 

 When caterpillars hatch in hollow trees or other dark 

 places, they invariably find their way out in a short time, 

 being attracted, as it is supposed, towards the light. To 

 determine how strongly the light influenced them in their 

 movements. May 6, 1895, twenty-five newly hatched cater- 

 pillars were placed in small pasteboard boxes which had a 

 small hole in each end. One end of each box was placed in 

 the bright sunlight, while the other end was shaded. In 

 an hour and a half all the caterpillars had emerged through 

 the holes in the ends exposed to the sun. 



Distance Young Caterpillars are able to Travel. 

 For the purpose of ascertaining how far from the egg- 

 cluster a newly hatched caterpillar can travel without feed- 

 ing, seven were placed on a large sheet of white paper on a 

 table. Their movements were traced by following them 

 with the point of a pencil on the paper as they crawled, 

 and these lines were carefully measured after the death of 

 the caterpillars. In their movements it was observed that 

 they showed a strong tendency to crawl towards the window 

 during the day, and towards the light of the lamp during the 

 night; but in no case were they observed to be attracted 

 towards food, however near it was placed, provided it did 

 not touch their hairs. The distance travelled by each cater- 

 pillar before it died was as follows : No. 1 travelled 90 1 

 feet; No. 2, 93 feet; No. 3, 143 feet; No. 4, 85 feet; No^. 

 5, 36 feet; No. 6, 46f feet; and No. 7, 144 feet; aver- 



