143 
Altho careful examinations have been made, I have never been 
able to find the common eel-worm root-galls on the plants at¬ 
tacked by the leaf-infesting species. 
Dr. E. Molz has published an article on this nematode in the 
Centralblatt fiir Bakteriologie, Parasitcnkunde, und Infcktion- 
krankheiten* in which he concludes that the species is dormant 
in the soil, and may enter the branches and leaves by being splashed 
upon them with the soil when syringing. In his experiments, 
sterilization with steam killed the nematodes in the soil. 
Preventive Measures .—In propagating plants liable to be at¬ 
tacked by leaf nematodes, it is first necessary that the soil be en¬ 
tirely freed from them, and for this purpose its sterilization by 
means of steam, as described on page 88, is the best method. It 
is also necessary that the plants front which cuttings are made 
be clean. With clean soil and plants to begin with, there should 
be no damage by these pests provided the tools are also clean. 
If plants are found infested, they should be removed and de¬ 
stroyed, as they are incurable. Eel-worms thrive best in a moist 
atmosphere, and it is desirable to keep the houses as dry as the 
well-being of the plants will permit. This can be better accom¬ 
plished by watering heavily at considerable intervals than by light 
and frequent watering. 
*Ueber Aphdenchus olesistus Ritz. Bos und die durch ihn hervorgerufene 
Aelchenkrankheit der Chrysanthemum. Centr. f. Bakt. Abt. II, Bd. XXIII 
(1909), pp. 656-671. Mit 1 Tafel und 2 Textabbildungen. 
