TURNIP BEETLES. 



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The head was purple or dark, with a shield-shaped marking pointing 

 towards the top, and the segments immediately behind the head, with 

 two patches reaching nearly to the middle of the back ; the succeeding 

 segments with one spot on each side, the three preceding the tail 

 with an additional spot in the centre, and the last segment with the three 

 spots confluent ; each segment was furnished with a bristle on each 

 side, excepting that next the head, which was furnished with two or 

 more. "When full grown the larva was whitish. 



The method of life, as I observed it on various plants of the 

 Cabbage kind, was as follows :— About the 6th of June Melifiethes were 

 to be found in great numbers in the blossoms, apparently feeding 

 entirely on the pollen (probably they had been about for some weeks 

 previously) ; shortly afterwards eggs and maggots were noticeable. 

 Tlie eggs were laid within the unopened buds, and the maggots were 

 to be found in profusion by the 17th of June in the buds and partially 

 opened flowers, which were distinguishable by their stunted and 

 shrivelled appearance. The maggots appeared to prefer feeding at the 

 base of the blossom; presently they spread from the flowers, and 

 might be found in parties of a dozen or two at the base of the stalks of 

 the topmost flowers ; others distributed themselves variously, but 

 chiefly on the seed-pods, where the gnawing motion of their brown 

 jaws might be clearly seen against the light colour of the vegetation. 

 Some of these maggots, which I had under observation, left the sprays 

 on the 17th of June (by falling down), and then buried themselves as 

 quickly as they could. About ten days later, I found the chrysahs 

 already formed in an earthen cell, about three and a half inches below 

 the surface of the ground. Probably in natural circumstances, and 

 the hard ground of a field, the maggots would not go so deep. 



I had not opportunity of observing the period which elapsed before 

 development of the beetles, and therefore complete the history from 

 the observations of Dr. Taschenberg, referred to above. The earlier 

 date of pupation is probably owing to the differences of Continental 

 climate, and it will also be noticed that he mentions the change to 

 chrysalis taking place in a Hghtly-spun web, which I did not notice 

 myself, but might possibly have overlooked within the earth cell. Dr. 

 Taschenberg notes :— " At the beginning of June they (the larvae) are 

 mostly fully grown ; they let themselves fall to the ground, and in ten 

 days turn, a little below the surface, within a lightly-spun web to the 

 pupal state, from which the beetles make their appearance in from 

 twelve to fourteen days. Tliese maybe found throughout the summer 

 on all the neighbouring blossoms so long as weather permits, and 

 then creep down into the ground for the winter." * 



* ' Praktische Insekeu-Kunde,' by Dr. E. L. Taschenberg, pt. ii., p. 11. . 



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