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Transactions. 



and in most cases cannot be removed without damage. The moths lay 

 throughout the summer right up till the end of autumn. The period of 

 incubation differs considerably : in 1912 a batch laid on 20th May hatched 

 on 18th June — that is, twenty-nine days ; while this year (1914) a batch 

 was laid on 26th March and hatched on 2nd April— only seven days. The 

 weather during the incubation of this last lot was exceptionally hot, and 

 this no doubt accounts for the shortness of the period. Eggs laid at the 

 end of autumn would, in the case of a cold winter, remain unhatched till 

 the following spring. The moth has a large egg-laying capacity, one in 

 captivity laying over 500 ova within a space of thirty hours. Egg-deposting 

 is carried on during the day as well as at night, though just at dusk is 

 preferred. 



The Larva. 



1st stadium : Duration, 27th March to 1st April, five days. Length 

 immediately after hatching, ^ in. Newly hatched : Colourless ; head, pro- 

 thoracic shield, and tubercles black. A day later the legs become black. 



Fig. A. — Larva: 1st instar. 1, prothorax (note position of iii, v, and vi ; iv absent); 

 2, metathorax (iv absent ; sp, snbprimary) ; 3, 1st abdominal segment 

 (note iii and absence of vi) ; 4, 2nd abdominal segment ; 5, 3rd abdominal 

 segment ; 6, 5th abdominal segment ; 7, 7th abdominal segment (a, pos- 

 terior subsegment). 



Note. — Here and in subsequent figures the segments are not drawn to scale, but 

 are lengthened in order to include all the tubercles. The whole importance has been 

 placed in the positions of the various tubercles. 



and, owing to the assimilation of food, the body is green. The thoracic 

 segments are darker than the rest of the body, while the last two abdominal 

 segments are blackish owing to the collection of undigested material 



