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APPENDIX. 
very frequently at the base of the stem on the inner side of the delicate 
sheaths by which the stem is surrounded. This species was not yet 
known as occurring in England. On these sheaths I also observed 
some specimens of Aphelenchus modestiis, de Man, both male and 
female; and the following species were moreover found, though some 
of them probably occurred in the adhering earth :— Monohystera 
simplex, de Man ; Mononchus papillatus, Bastian ; Mononchus hidentatus, 
de Man ; Cephalohus striatus, Bastian ; Plectus granidosus, Bastian .(see 
fig. 3, p. 36 of this report); and P. cirrhatiis, Bastian.” 
With regard to the three species figured (from Dr. Bastian’s 
Monograph at page 36, to give some idea of differences of structure in 
various kinds of Eelworms), Dr. de Man mentions that he “ had found 
Plectus granulosus to be one of the commonest species, living in the 
soil, and distributed throughout the whole of Western Europe.” 
“ Tylenchus obtusus is most closely allied to T. duhius ; the latter species, 
however, is nearly as common, and as widely distributed” in the soil 
as the Plectus granulosus. “ Aphelenchus arena, however, hitherto was 
never,” Dr. de Man observes, “ found by me in the soil, and I presume 
that it inhabits the plants without causing a disease.” 
The following notes give some additional information as to methods of 
prevention and habits of this Eelworm, with ivhich I have been 
favoured by Dr. J. Ritzema Bos :— 
“ As soon as the ‘ stem-sick’ Eye begins to die, and the haulm to 
turn yellow (as during the ripening of the Corn, but often much 
earlier), the Tylenchi begin to wander from the upper to the lower 
parts of the plants, to finally leave the plants and live in the ground 
(usually in a sfete of suspended animation). Thus the Tylenchi begin 
to travel directly the plants begin to die, and much sooner. But 
directly the plants are entirely dead, or dried up, the Tylenchi c,?mnoi 
travel farther, because they pass into a state of torpidity in the dried 
tissues. Thus, because during the ripening of the Eye and the 
withering of the plants, most of the Tylenchi wander from them into 
the earth, the earth thus becomes infested. But as all the Tylenchi 
have not been able to leave the plants before the complete withering 
or ripening, the straw and also the stubble will always contain a 
greater or less amount of these Eelworms, more especially as during 
the ripening of the Eye eggs of this Eelworm are still to be found in 
it, which of course cannot wander away.”—J. E. B. 
Therefore, as is jiointed out by the Professor Dr. J. Eitzema Bos, 
above quoted, the stubble cannot be ploughed in without danger, 
because there is still presence of Eelworms in it; and if it is burnt 
directly the crop is cut, though we get rid of those that are in the 
stubble, there are still the great number which have travelled into the 
