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it was found to be due to species of nematodes popularly known 
as eel-worms. This spotting is very characteristic, and appears 
on the surface of the leaves as brownish, more or less circular 
blotches, which gradually enlarge and become irregular in outline. 
When the infestation is had the leaves curl under and soon fall 
from the plant. Not only is the beauty of the plant ruined, but 
the dropping of the leaves and the loss of vitality keep it con¬ 
tinually stunted. 
Perhaps the first record of these foliar eel-worms in America 
was that of Professor Byron D. Halsted*, who found them in the 
leaves of chrysanthemum. He has written on foliar nematodes 
in various issues of Garden and Forest, and also in several re¬ 
ports of the New Jersey Agricultural Experiment Station. He 
has reported finding them, in New Jersey, in the leaves of chry¬ 
santhemums, Coleus, Bouvardia, Lantana, Begonia, Pelargonium, 
Salvia, Zinnia, moonflower, fern, and Ficus carnosa. Specimens 
in infested leaves of the first three named plants were examined 
for Professor Halsted by Professor Geo. F. Atkinson, who called 
them a new species of eel-worm, which he placed in the genus 
Aphelenchus. Mr. Wm. C. Sturgis has reported finding eel-worms 
in Connecticut in the leaves of asters.f This nematode also was 
examined by Professor Atkinson, who determined it as a species 
of Aphelenchus. These are the only original records of leaf-infest¬ 
ing eel-worms to which T have access. 
The worms causing this leaf injury are very minute, elongate, 
somewhat pointed at each end, and semitransparent. According 
to our observations they reach the plant thru the soil. Mr. J. A. 
Valentine, of Denver, Colorado, to whom I wrote inquiring 
whether plants propagated from healthy stock showed the char¬ 
acteristic disease, replied that his foreman “propagated from ap¬ 
parently clean stock which was secured from J. A. Peterson, of 
Cincinnati. The stock propagated from these clean plants shows 
this same trouble, altho not to the same extent as plants which 
were propagated from stock already infested.” Thus it would 
appear that infestation originated either from the soil, from the 
tools used in the work, or from the water used in spraying the 
plants. If infestation is from the soil, as is our supposition, it is 
probable that the eel-worms crawl up the stems of the plants, 
while the latter are small, and at the time when the stem is moist, 
—for example, during or immediately after syringing. Or they 
may be washed up from the soil on to the leaves when syringing. 
*Nematodes in the Chrysanthemum. Garden and Forest, Vol. TIT., Oct. 
15, 1890, p. 499 - 
f A Disease caused by Nematodes. Ann. Rep. Conn. Agr. Exper. Station, 
for 1892 (1893), pp. 45-49- New Haven. 
