Mr. Hardy's Entomological Notices for 1869. 81 



being found in some seasons in very exposed upland fields 

 on turnips of all sorts. Closely applied to the leaf, and 

 placed among the densely packed myriads of Aphides, were 

 several leech-like larvae. These " Aphis-lions," for such in 

 effect they are, although blind, grope about, seize hold of the 

 lazy Aphides and suck them to death ; never leaving off ex- 

 hausting victim after victim till they are full grown. After- 

 wards they take the form of a straw-coloured tumour ; and 

 finally develop a gayly banded fly of the genus Syrphus ; a 

 fly often seen hovering in the sunshine over the summer 

 wild flowers. Useful as they are, they are quite inadequate 

 to keep within bounds the swarms of living young at the 

 inordinate rate with which the Aphides increase. At the 

 period when I received them, the Aphides had arrived at 

 the last living generation for the season. They were acquir- 

 ing wings preparatory for migration ; and that winged race 

 deposits eggs, and not living offspring, to perpetuate the 

 species. They and all the wingless forms perish in the early 

 frosts. In my own vicinity there has been a scarcity of 

 Aphides ; and what is somewhat singular we have had no 

 autumnal migratory flights of any kind of these insects. 



The other occupants of the leaves were the caterpillars of 

 the common Cabbage Butterfly (Pontia brassicce), and the 

 green caterpillar of the small White Butterfly {Pontia rapes'). 

 From the monthly notices in the " Entomologist," it appears 

 that the large White Butterfly has been scarce this summer 

 in the south of England. There was no deficiency here- 

 abouts ; but the caterpillars were more numerous in 1868 

 than in 1869. About the beginning of harvest there suddenly 

 appeared large numbers of the Pontia rapce in the turnip- 

 fields. They left a few caterpillars, but little damage resulted. 

 This had not been an instance of local increase, for my friend 

 Mr. Bold writes me from the neighbourhood of Newcastle : 

 " On the 24th August we had a sudden appearance of hosts 

 of small White Butterflies, all Pontio rapce. The gardeners 

 turned to and slew them in thousands ; my brother killed all 

 day, and said that a hundred individuals were often in view 

 at one time in one small garden." 



We were not affected this year with the small green cater- 

 pillars of the Diamond Moth (Plutella cruciferarum), which 

 make such havoc on the leaves, by cutting them up into 

 small holes during the drought of summer, when growth is 

 at a stand. I have remarked that, about that period flocks 



B.N.C. — VOL. VII. NO. I. L 



