190 THE ENTOMOLOGIST. 



They were laid in irregular rows on the sides of a chip-box, with their 

 longest sides touching each other. Their colour was a dark, almost 

 coffee-coloured brown. Although they were kept indoors, but in a 

 cold room without a fire, throughout the winter, hatching did not 

 begin until May 21st of the following year. On that date a single 

 caterpillar emerged, and nine days afterwards the rest followed suit. 

 It appeared, even through a lens, to be nothing more than a thin 

 greenish but very animated line. It grew apace, and kept the start it 

 had made to the end of the chapter. It spun up on June 30th, and 

 appeared as a fine big female on July 21st. From May 30th, hatching 

 continued daily and gradually until June 29th, when all the larvaB 

 had appeared. These I fed on ash leaves, always taking care that the 

 latter were fresh. Once I tried the larvfe on birch. They ate a little, 

 but evidently preferred ash, so I troubled them no more with experi- 

 mental foods. The eggs were hatched in large glass jars placed out 

 of the sun with pieces of muslin kept stretched over the tops by elastic 

 bands. A piece of glass was then laid so as to almost cover the muslin, 

 but just leaving so much uncovered as would allow for ventilation. 

 The glass over the tops of the jars preserves the food-plant wonderfully. 

 I may add that the larva were kept in these jars until they pupated. 

 The only change I made was the substitution of net for muslin, or 

 gauze, as the larvse grew. After pupation the spun-up chrysalids were 

 placed in deep card-boxes about a foot square to give the expected 

 moths plenty of room. The caterpillar itself I found to be continuously 

 green — head, segments, legs, and claspers — until the stage before the 

 final one. The particular shade of green is exactly that of the ash- 

 leaf. The protective coloration is therefore remarkable, and doubtless 

 supplies an escape from birds as well as from the eyes of most observers. 

 Besides, the larva rests, as a rule, on the under surfaces of the leaves, 

 along the midribs and veins, with which it assimilates marvellously. 

 Since ash trees are usually exposed to every wind that blows, the 

 caterpillars are furnished with large and powerful anal claspers, 

 enabling them to exercise a tenacious hold. They spin a silken thread 

 which they freely use, especially in the earlier stages, as a means of 

 locomotion. In the third stage they perhaps assimilate most with the 

 yellowish green of the leaves, leaf-stems, and midribs, and the seg- 

 mental divisions of the caterpillar are distinctly yellowish. In the 

 fourth stage the appearance of the caterpillar is as follows : Length 

 If inches. Hazel or hazel-green. Segment divisions russet. Head 

 green or hazel-green. Legs and claspers dark russet. Three con- 

 spicuous dark russet warts on body — the first on segment 3 ; second 

 on segment 6 ; third on segment 9. Although the protective coloration 

 is to some extent lost, or perhaps it would be more accurate to say 

 changed, at this period, it distinctly returns in the final one. The 

 caterpillar once more assumes the green of the ash-leaf, the dark tint 

 of the segment-divisions is gone, and that of the humps almost so. It 

 then draws two or three leaflets together, like Geometra j^pilionaria, 

 using a few strong, short and netted, white, silken threads. Here it 

 changes to a pale green, stout, and anal-pointed chrysalis. I only 

 saw one case of cannibalism. Throughout they were reared in a cool 

 room without a fire ; all had spun up by July 21th, and all had 

 emerged by August 21st. There were a few exceptions — perhaps a 



