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HAM AM ELIDE 



economy of the insect, which has been too much over- 

 looked. Again, it is staged that no period of sowing 

 is too late, provided the weather be warm, for the 

 attacks of the insects; hence the season for the ravages 

 of the insect may be said to coincide with the season 

 of vegetation itself. As to the stage of growth of the 

 plant, it appears clear that the mischief is caused 

 during the growth of the cotyledon leaves ; if the 

 plant is sufficiently strong to put on its second series 

 of rough leaves, the insect, although it may continue 

 its attacks, has not sufficient power to do much 

 damage. It likewise appears that it is in hot, and 

 especially in hot damp weather, that the insect is 

 most prejudicial. As to soils, the correspondents 

 agree that no soils whatever on which turnips can be 

 (-iikivated at all are free from the insect ; and in like 

 manner no manure at present known will prevent its 

 approach, although that manure which most effectu- 

 ally promotes the rapid growth of the plant, and the 

 throwing out of the rough leaves, will at the same 

 time be the most effectual defence against the insect. 



Turnip Fly. 



As to the mode of sowing to be adopted, the answers 

 are decidedly in favour of the drill system over broad 

 east, by bringing the plant more immediately into 

 contact with the manure, and by forcing forward the 

 plants from the thickness in which they stand in the 

 rows ; and lastly, that regular management, and a 

 high state of cultivation, are highly important in en- 

 suring regular success, lands in the best condition 

 escaping best. The turnip-fly, moreover, feeding 

 also upon many hedge weeds, and sheltering itself in 

 rough grounds, nothing would tend more effectually to 

 prevent its accumulation than by early clearing off both 

 its shelter and food as far as possible. Thus much is 

 given as relates to the attacks of the insect, but of its 

 natural history no decisive information was obtained 

 by the Doncaster Agricultural Association. It is said 

 that " this part of our inquiry is by far the most im- 

 portant; and, important as it is, cannot in the present 

 state of information be fully answered." Can it be 

 doubted that this is not the most important part of the 

 inquiry ? How is it possible that successful remedies 

 can be applied whilst some persons assert that the 

 insect is produced from eggs placed by the parent 

 beetle upon the turnip seed, and others that it is 

 thrown into the earth with the manure ? The report 

 proceeds: " Under these circumstances all speculations, 

 as to the abode and habits of the infant turnip-fly, 

 must be vague and unsatisfactory. We need not say 

 how very important it is that these facts should be 

 ascertained, and that we should know where the 

 enemy is generated and nurtured, as well as the length 

 of time occupied in each transformation. An exten- 

 sive series of experiments undertaken on this subject 

 might be of the utmost advantage, and eventually 

 prove a national benefit. It is possible that in its 

 infant stages the insect may be destroyed more effec- 

 tually than in any other ; and at all events an accurate 



knowledge of these facts would confine the efforts 

 and experiments of the farmer within certain limits, 

 from which they must now, in our ignorance, be con- 

 tinually diverging, and much time and effort now 

 wasted on impossible experiments would be saved." 

 To this, therefore, the natural history view of the 

 question, it is our duty to direct, in an especial manner, 

 the attention of our readers. 



It only remains for us to notice the most advisable 

 remedies suggested for preventing or alleviating the 

 attacks of the insect. Of such as relate to the steep- 

 ing of the seed, or the mode of the sowing of the seed, 

 we are silent, as it is quite clear, from what is known 

 of the habits of the insect, that they are untenable, 

 save as relates to the more quick forcing of the growth 

 of the plant. An expedient which seems partially 

 successful consists in sowing with the turnips the 

 seeds of some other plant, which may be more grateful 

 to the taste of the insect, as when Swedes and white 

 turnips were sown together the former escaped. Fu- 

 migation and the burning of stubble on the wiadwaid 

 side of the field has been found to answer, as has also the 

 scattering of vegetable ashes or soot upon the plants ; 

 repeated watering of the plants also, where practicable, 

 has been found successful ; but the most universally 

 practised method, and apparently much more certain 

 of success, is to spread quick lime over the young plant, 

 as soon as out of the ground, spreading it on and around 

 the plant, and repeating: it as often as wind and rain 

 shall have cleared it off, until the plant be out of 

 danger. Lime is so common that it can be had in all 

 situations, and it is so cheap that the cost need not 

 embarrass the farmer. The labour is so comparatively 

 small that it is capable of being generally adopted, 

 and if the fly should not appear the lime can be used 

 for other purposes. It seems also to be advisable 

 that the lime should be laid on in a hot state rather 

 than after it is slaked. It would be easy and very 

 desirable that it should be spread by some machine 

 rather than by the hand. Some of the correspondents, 

 indeed, urged an objection against this plan, that the 

 quick lime injures the plant and prevents its growth, 

 but from the more decided observations of others, the 

 Association recommend " That as soon as the plant 

 appears above ground it be dusted with quick lime, 

 and this repeated as often as rain or wind beats it off, 

 and the fly re-appears." 



We hadi written thus far when we ascertained that 

 the Entomological Society of London, by whom the 

 turnip-fly had been selected as the subject for one of 

 the prize essays established by the society, has just 

 received an account of the insect in question, from 

 the pen of Mr. Le Kenx, in which an account of the 

 preparatory stages of the insect is given. The parti- 

 culars of this communication, read at the last January 

 meeting of the society, have not indeed transpired, 

 but we trust that the society will lose no time in 

 laying before the public a document which may prove 

 of such vast importance to the agriculturist. 



HAMAMELIDE^E. A small natural order, 

 containing only two genera, and about half a dozen 

 species. The Hamamelis is the Witch Hazel of 

 North America ; and the other genus is the Pother- 

 gilla from the same country, both hardy shrubs and 

 common in our collections. Both are increased by 

 layers. Little is known of the general properties of 

 these plants. The bark of the H. Virginica, which is 

 bitter, has been used medicinally ; and poultices 

 made of it are sp.id to relieye inflammatory tumours. 



