182 TOMATO. 



The enormous amount of Eelworm presence in the galls was 

 enough to spread infestation in the earth, and to all plants near 

 capable of receiving it ; but before giving further detail of this, and of 

 the attempted measures for checking it, the following information, 

 taken from the careful observations by J. C. Neal * on the commence- 

 ment of the attack by the " invasion" of the wormlets from the earth, 

 and its effect, deserves careful study. 



Method of spread of infestation. — This may be in various ways. 

 The Eelworm, when it comes into active life, may find its way through 

 a crack out of the gall, or it may make its way into the surrounding 

 tissues ; or (it is stated) it can use its head end, aided by the spear, to 

 pierce a way, firstly, out of the part of the gall in which it has 

 developed ; and, secondly, into the part of the root where it purposes 

 to establish itself. 



These operations I have not yet had the opportunity of observing in 

 our British specimens, but one method of spread of infestation on a 

 large scale was shown by the vast quantity of galls sent to me in De- 

 cember last. In these the contents of the infested gall were set free by 

 the peeling off of the outer coat or bark of the so-called Root-knot. 



Eeference to the Plate will show the different conditions of the 

 galls. Many of these were still perfect, but some, and notably one 

 (fourth from the outside of the lower part of the figure, right-hand 

 side of the Plate) will be seen to show the edges of the harder and 

 more durable parts of the altered cells, of which the gall is composed, 

 now free from the protecting bark. As in the galls which I opened, of 

 the large numbers of which the bunch figured are samples, I found 

 quantities of the infestation, with the Eelworm-shaped part of it 

 showing its live condition by its power of movement, it is presumable 

 that the eggs, and the egg-laden females (although from their shape 

 their live condition was not similarly noticeable), yet were also alive, 

 and well capable of continuing infestation. 



In regard to the very important point of attack to rootlets taking 

 place from " Root-knot " Eelworms wandering free in the soil, it is 

 thus i-ecorded from his own observations, by Dr. Neal.t "I have 

 found mature worms, males and non-pregnant females, in rootlets 

 but a few days old, and under circumstances which involved the 

 necessity of invasion from without the root." 



These Anguillulce, Dr. Neal notes, were small enough to enter the 

 stomata of epidermal tissues, and he thinks it "not unreasonable to 



* See ' The Root-knot Disease of the Peach, Orange, and other plants, in 

 Florida,' by J. C. Neal, Ph.D., M.D. Washington: Government Printing Office, 

 1889. 



t See Eeport by Dr. Neal, previously referred to, p. 12, 



