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of destroyers. So complete and so rapid was the destruction in some 

 instances, that a whole field was found, in two or three days, to pre- 

 sent only an assemblage of skeletonized leaves ; and this too when 

 the turnips had attained a considerable size. 



The insect whose proceedings have been thus briefly noticed, be- 

 longs to the Hymenopterous family Tenthredinida ; it is the Athalia 

 CentifolicE, a species first noticed by Panzer. Mr. Yarrell describes 

 the perfect insect and the caterpillar ; and then recurs to the damage 

 effected by the latter. By their repeated broods the devastation was 

 continued for so long a time that even the third sowing did not in all 

 cases escape destruction ; and it was not until the occurrence of the 

 heavy rains in September, terminating the unusually dry summer, 

 that the mischief ceased. The destruction of the leaves caused, in 

 most instances, the loss of the root also ; and where the leaves suf- 

 fered from the attacks of the black caterpillar, but not sufficiently to 

 occasion the death of the plant, the turnip itself became pithy and 

 of little value. It has become necessary, Mr. Yarrell states, to im- 

 port the root largely from the Continent to supply the deficiency of 

 the home crop. 



The remedial measures adopted on a former visitation were the 

 turning into the infested fields of a large number of ducks, who 

 greedily devoured the caterpillars as they were brushed from the 

 leaves by a boy with a long pole ; the passing of a heavy roller over 

 the ground at night, when the caterpillars were at their feed ; and 

 the strewing of quick lime by broad cast over the fields, renewing 

 it as often as it was dispersed by the wind. The latter mode was 

 generally considered as the most effectual preservative. 



