17 



CLOVER. 



"Stem-sickness" caused by Stem Eelworms. 

 Tylenchus devastatrix, Kuhn. 



Tyltcnchus devastatkix, Stem Eelworms. — Anterior portion of female showing 

 mouth-spear ; and embryo in egg ; all greatly magnified : anterior portion magnified 

 440 times. From figures by Dr. J. Eitzema Bos. 



lu the course of the year 1897, " Tuhp-root " appeared to be more 

 than usually prevalent in the Oat crop, and during the early part of 

 1898 much more inquiry was sent than is generally the case as to the 

 cause of the serious failure of Clover in various parts of the country. 

 Whether there was any connection between the attacks I cannot tell, 

 but in a large proportion of the cases in which specimens of diseased 

 Clover were sent to me for examination, I found them to be suffering 

 from infestations of the "Stem Eelworm," Tylenchus devastatrix, whioh. 

 also cause much mischief by giving rise to the attacks known as 

 Tulip-root and Segging in Oats. 



The dates of inquiries in the past season (1898) ranged from 

 January 26th to April 4th, and were from various parts of Yorkshire 

 and Lincolnshire ; likewise from localities near St. Ives, Hunts ; 

 Peterborough, Northamptonshire ; Hollesley Bay, Suffolk ; Eochford, 

 Essex ; Edenbridge, Kent ; and Malvern, Worcestershire. 



In almost every instance specimens of the diseased plants were 

 sent for examination, and in about three cases I found outside the 

 roots some amount of the white maggots of the well-known Clover and 

 Pea Leaf Weevil (Sitones, scientifically), which sometimes do much 

 harm at Clover roots, but (in the above instances) were far too few in 

 number to account for the serious amount of mischief present. These 



c 



