THE ENTOMOLOGIST 



Vol. XXXVII.] JUNE. 1904. [No. 493. 



ON NYSSIA LAPPONARIA. 



By E. a. Cockayne. 



Plate VI. 



Last spring I had hoped to have published some observations 

 on the habits of Nyssia lapponaria. Unfortunately, a bitter cold 

 north-west wind raged the whole time I was in the Eannoch 

 district, and I only saw a single male and four females. This 

 season I have been more fortunate, and hope the following notes 

 will be of interest. 



The ova are laid during the day in any deep chink, in batches 

 of 10 to 150. The female walks slowly up anything which grows 

 in the marshy ground they inhabit, probing with her extremely 

 long ovipositor until a suitable place is found. I have actually 

 observed wild females laying in reeds between the stem and outer 

 sheath, in a crack in a dead bracken stem, and under flakes of 

 bark on fallen sallow twigs ; but the most usual place is un- 

 doubtedly in the dry brown corollas of the cross-leaved heath 

 {Erica tetralix). 



This last, with bog-myrtle {Myrica), appears to be the 

 favourite food of the larvfe, which hatch from May 20th to the 

 30th, and are full-grown at the beginning of July, a few lingering 

 on to the end of the month, or even till the second week in 

 August. The pupas lie very near the surface, and are quite 

 without cocoons. Out of doors they probably always remain 

 two years in this state ; but in the house many emerge after one 

 winter, and can easily be recognized, since in them the insect is 

 fully formed a month or two after pupation, and they become 

 very dark in colour. They are very sensitive to changes of 

 temperature, and a cold night will prevent any from emerging. 

 This, and their power of remaining in the ground till a more 

 favourable season, probably explains the extreme irregularity of 

 their appearance. 



During the day they sit on the top of the bell-heather and 

 common ling, frequently paired or a male and female close 

 together, or about half-way up the stem of a bog-myrtle, with 



ENTOM. — JUNE, 1904. 



