34 FIELD AND FOREST. 



there will be myriads. If these numbers reach such a pitch as to dete- 

 riorate the crops the remedy is plain. Change the rotation and grow 

 some other crop instead of wheat. Most of the wheat insects are only 

 annuals. If they could be banished for one year they would be ban- 

 ished entirely, or until re-introduced. Now, if there were a con- 

 trolling authority, what would be easier than to say to the Farmers, 

 "Gentlemen, in the common interest you will substitute barley for 

 wheat in your next year's rotation." The insect, deprived of its 

 proper nidus, must then either lay its eggs in an unsuitable place 

 where they will perish, or have recourse to the pasture fields for Triti- 

 cum repens, or other suitable grasses. By this of course the fly would 

 not be exterminated, but its numbers would be so reduced as to ren- 

 der it comparatively harmless, at all events for a time, when if it 

 again re-appeared in force, the same means of defense would be resor- 

 ted to. Nay, it might be so arranged that two or more countries 

 might brigade themselves together, so as to establish a permanent see- 

 saw by which they should play into each other's hands. But no sin- 

 gle man can carry out such a rotation. He may try it upon his own 

 fields, but they will be replenished continually from the fields of his 

 neighbors, unless they at the same time are compelled to follow the 

 same rotation. 



Mr. Murray then went over the various other means of extirpation, 

 picking and burning infected plants, the collecting caterpillars, poi- 

 sons and local remedies, in relation to which he drew attention to the 

 destruction of what are called ticks and lice upon sheep. Every one 

 knows how readily such vermin can be communicated by contact or 

 proximity, and it does seem a very hard case that a man, who has 

 kept his flock clean by proper precautions, should be liable to have 

 infected by a neighboring neglected flock, by stray sheep or even by 

 sheep passing along the road. It is said that, ccetetis paribus, the 

 difference in value between a sheep that has been kept clean for the 

 season and one that has been worried by vermin will be 20s. If that 

 is so it is a wonder that sheep farmers have not long since clamoured 

 for some supervision. 



At the conclusion of the paper the following resolution was put 

 from the chair and carried : — "That thanks are due to the President 

 and Lords of the Council for having brought the subject of insect 



