EELWORM GALLS 
”3 
Economic Notes 
It will be apparent from what has been written that 
the majority of gall-causing eelworms are troublesome 
pests ; there is, moreover, always the possibility that species 
now infesting plants of little economic importance may 
establish themselves upon cultivated ones. 
Worthington G. Smith recorded in the Gardeners 
Chronicle , 1886, vol. xxv., p. 41, the presence of little 
black spherical galls on the leaves of an Odontoglossum, 
which were caused by an eelworm. 
Miss Ormerod, in 1891, observed galls on Vicia Faha 
Linn, caused by Tylenchus devastatrix. The stem is short¬ 
ened and bears pronounced irregular swellings. 
There are numerous Continental records of galls on mem¬ 
bers of the family Liliaceae caused by Tylenchus devastatrix. 
The evidences of attack are slight in many cases, but there 
is undoubted hypertrophy and consequent weakening of the 
plant. 
Heterodera radicicola does much mischief on the Continent 
amongst cultivated varieties of Clematis and various 
Rubiaceae (notably Gardenia , Coffea , Ixora , and Hamiltonia ), 
causing nodosities to arise on the roots. 
For detailed particulars concerning the stem eelworm 
( T. devastatrix) and the Wheat eelworm (T. tritici), the 
reader should consult the second edition of Miss Ormerod’s 
“ Manual of Injurious Insects,” and Leaflets 46 and 75 
issued by the Board of Agriculture. 
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