LECTURE ON ENTOMOLOGY. 65 



these two is a measuring worm, wliich lays its eggs upon the stem 

 and branches of the bush, where they remain all winter and ma}^ be 

 found and destroyed. Bushes from the nursery should be examined 

 so that the insect ma}- not be introduced into places now exempt. 

 The latter is of European origin and has of late been so destructive 

 as to be known as the currant worm. The perfect insect comes out 

 of the ground in May, and finds the leaves ready ; it lays about a 

 hundred eggs on the under side along the principal veins, where 

 they can be seen by turning up the leaves, which should be plucked 

 off and burned. This is the easiest method of destro3'ing this in- 

 sect. If the eggs are allowed to hatch, the worms immediately begin 

 eating the leaves, at first making little holes, which they soon en- 

 large, afterwards eating the edges, and then going to other leaves. 

 The worms should be gathered and crushed or thrown into boiling 

 water. When they have finished eating they go into the gTound 

 and form a cocoon near the surface, or under leaves. If the ground 

 is smooth and hard under the bushes, or if boards are laid over it 

 they are, in a measure, prevented from doing this. There are two 

 broods in a j'Car, the second being much more numerous than the 

 first. The earlier they are attacked the better. These details will 

 serve as a specimen of the treatment which injurious insects ought 

 to receive. 



These five are the most important enemies of our currant and 

 gooseberry bushes, but a large number of others are known, which 

 do, at times, very severe harm to the same bushes. 



A repetition of the descriptions of these insects, would only add 

 to the large number of times the same have been described. Ex- 

 perience has shown that httle attention is, as indeed from the nature 

 of the case must be, paid by practical horticulturists to accounts of 

 the habits and descriptions of the forms of these insects, for while 

 the description itself might be simple, the interpretation of it re- 

 quires some knowledge of the several tens of thousands of other 

 insects found also in this country. By way of illustration, Mr. 

 Mann drew a parallel between the practice of economic entomology 

 as a profession, and the practice of medicine. While ever}'' person 

 might be competent to study the nature of any one disease, and to 

 administer the proper remedies, the very great number of diseases 

 and the necessity of immediate readiness to cope with any one, made 

 it only possible for persons who devoted their whole attention to 

 the subject to undertake the task of practising medicine. So it is 

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