THE ROOT-KNOT EELWORM. 3 



as indicating the abundance of any particular insect or insects, 

 the extent of their depredations, the plants affected, means 

 of distribution, and causes facilitating the spread of insect and 

 other pests. 



It is specially desired to obtain the services, observations, 

 and experiences of those practically acquainted with insects 

 and other agricultural pests. 



Each worker will receive due credit for all observations, 

 etc., and a copy of all future Reports ; further, all inquiries for 

 information will be willingly answered. Appropriate stationery 

 and stamped and addressed envelopes will be supplied to those 

 selected. 



NEMATODA. 



THE ROOT KNOT EELWORM. 



Heterodera radicicola. 



The Root-knot Eelworm was first reported in this country in 

 1892 by the late Miss Ormerod, from Kent, infesting the roots 

 of tomato and cucumber plants. At that time it was hoped that 

 the climatic conditions in this country would prove uncongenial 

 to this worm as a pest to farm-crops, and to within a couple of 

 years ago it seemed likely that these hopes would be realised. 

 In October, 1902, however, Mr. Cecil Warburt on ( l )" received 

 from Kent specimens of swede plants undoubtedly suffering 

 from root-knot disease, and containing large numbers of the 

 characteristic worms." 



The importance of this discovery is of the greatest moment 

 to agriculturists for, as Mr. Warburton pointed out : " It 

 would appear as though the only condition hitherto wanting 

 were the chance conveyance of the worm to crops grown in tha 

 open, and now that this has come about the consequences may 

 be very far-reaching. Infested cucumber and tomato beds 

 acquire very much greater importance as the possible centres 

 from which disastrous attacks on farm crops may be spread, 

 and a disease which has aroused no great interest in this country, 

 except amongst market gardeners and nurserymen, becomes a 

 danger with which the farmer will have to reckon." 



I have quoted Mr. Warburton at length, as the case I have 

 to record fully bears out his view as to the method of conveyance 

 to outdoor crops. 



A Staffordshire correspondent invited me to inspect some 

 vegetable marrows, which, " in spite of every care and attention, 

 were gradually going from bad to worse." 



The first examination revealed nothing beyond the fact 

 that the leaves were shrivelling and turning yellow, and generally 

 the plants looked very sickly. In mentioning what he .had 

 done to improve the ground, my correspondent informed me 



i. Journ. Roy. Agr. Soc., 1902, vol. 63, p. 299. 



