DIMORPHA VERSICOLORA. 247 



May 6th and 7th. In second stadium, larvae fed in groups of 4 

 or 5, rested again for 36 hours, and moulted May 16th and 17th. 

 In third stadium, larvae fed solitarily, the resemblance in size and 

 general appearance to birch catkins most striking, rested 48 hours 

 and entered upon the fourth stadium from May 26th to 28th ; fed on 

 solitarily, rested when fullfed in this instar from 48 — 60 hours, and 

 entered the fifth stadium from June 6th — 8th. On June 18th the three 

 most advanced larvae presented a very handsome appearance, a pro- 

 nounced pink blush mingling with and almost killing the former green 

 hue ; within twelve hours these larvae commenced to form their cocoons. 

 The whole spun up between June 18th and 23rd. The most forward 

 individuals occupied the following time to complete the larval 

 stage : 1st stadium, 12 days, 2nd stadium, 10 days, 3rd stadium, 10 

 days, 4th stadium, n days, 5th stadium, 12 days = 55 days altogether. 

 Buckler notes that a batch of newly-hatched larvae that he reared 

 showed a disposition from the first to feed at intervals on two 

 particular leaves near the top of a spray of birch whereon they had 

 all assembled, holding to the twig by their ventral anal prolegs only, 

 the fore-part of each body being bent back away from the twig, 

 leaving the anterior legs free ; after the second moult they were 

 an inch long, and then broke up their society and separated for 

 independent existence, yet were sufficiently amiable whenever they 

 chanced to find themselves near each other to agree perfectly well at 

 any time ; while resting they still elevated the. front part of their 

 bodies as when younger ; after the fourth and last moult their docile 

 behaviour continued to be remarkable, as they showed no disinclina- 

 tion to be handled, but grew quite lethargic, often sleeping side by 

 side contentedly like so many fat pigs, but when awake they made 

 good use of their time, consuming a great quantity of birch, and their 

 growth was commensurate. He further observes that, when fullfed, the 

 larva becomes restless until it finds the moss and leaves needful for its 

 retirement and the construction of its cocoon. Weaver records that he 

 found, on June 30th, 1 845, eleven larvae feeding on one leaf at Rannoch, 

 and that, on being disturbed they threw up their heads and bent their 

 bodies just as do the larvae of the Tcnthredo. The eggshells from 

 which these had hatched were arranged in a double row around one 

 of the twigs. Chapman notes that very young larvae in their early 

 gregarious stage pine and refuse to eat when solitary. Holland 

 says that when the newly-hatched larvae emerge they arrange them- 

 selves neatly on the twigs, and when at rest, side by side, completely 

 encircle the twig, attached only by their claspers, with the front 

 segments thrown back. They are black-looking little things at 

 first, but gradually become green, and then rather conspicuous, 

 much like a bunch of sawfly larvae, particularly when the twig is 

 touched. They are gregarious till the last moult but one, only as 

 they get larger a fewer number usually go to form a bunch, and 

 what was at first one bunch will form two. When they break up 

 altogether they wander a good bit, and seldom more than 3 or 4 

 are found on a bush, and these usually on the higher parts, looking 

 now very like the great green catkins on the birch at this time. 

 They will fall to the beating-stick, but searching pays best. June 

 (early) is the best time to look, as the larvae have reached a good 

 size and vet not separated ; even after the companies have broken 

 up and wandered, searching seems best, as stripped twigs then show 



