79 



thrown over them ; otherwise the pupre may have had times to 

 become moths, and the trouble will have been in vain. 



I "will conclude with a few remarks on the report of the select 

 committee recently appointed to enquire into the subject. 



1. In reply to the query about removing the bark, I would 

 suggest that this be done to all trees with rough bark as soon as it 

 is known that the grubs have entered the chrysalis stage, the bark 

 thus removed to be burnt. Then I would apply the bagging before 

 mentioned, not later than early next spring, when the blossoms 

 begin to appear. By the removal of the bark the grubs will be 

 compelled to spin in or under the bagging and be all the more 

 surely detected. 



2. The grub could undoubtedly travel some distance, but is sure 

 to remain at the first suitable shelter it meets with. 



3. I do not think it necessary for the fruit to fall. Most of these 

 larva} can lower themselves by a silken thread. 



4. The grub requires a shelter of such kind as to allow of its 

 forming a cavity therein, in which to spin its cocoon, therefore 

 the traps ordinarily used for earwigs Arould be of no use whatever. 



5. The particular insect reported on attacks only apples and 

 pears. 



6. This query is already answered above. 



For the following reasons it is impossible that any information 

 resulting from the enquiry in Portugal into the natural history of 

 Phylloxera vastatrix can be of any use in regard to the best means 

 of destroying the Codling Moth : — 



The Phylloxera belongs to a different order of insects — namely, 

 the Homoptera, family Aphidae, or Plant-lice, of which the ''green 

 fly " on rosetrees is a familiar example. They are suctorial insects, 

 destitute of jaws, living upon the juices of plants, which they absorb 

 through their proboscis or sucker. 



Their trarsformations are quite different from those of the 

 Lepidoptera, they being active and resembling the perfect insect 

 in both the larval and pupa stages. 



Their mode of propagation is quite abnormal, and different from 

 that of all other orders of insects. As this is highly interesting 

 and probably not generally known, I quote a short extract on the 

 subject from Professor Westwood's Introduction to the Modern 

 Classification of Insects : — "Each family of plant-lice in spring 

 and summer consists of individuals always wingless, and of pupre ; 

 all these, however, are females, which produce living young with- 

 out a previous union with the other sex ; and Bonnet, whose 

 researches have removed all doubts upon the subject, has clearly 

 shown that this power is exercised at least through nine generations, 

 which are produced within the space of three months. Whilst 



