From the study of the worm egg output of nearly fifteen hundred sheep on many hill farms in Scotland it has been shown that:-

(i) Worm egg output in ewes and gimmers is lowest in early winter and highest in spring and early summer; this is followed by a marked decrease towards the winter months.

(ii) Generally in ewe hoggs the worm egg output is the same as that in older sheep, but shows greater variability; on occasion the spring peak may be absent.

(iii) The level of worm egg output of hoggs is generally higher than that of older sheep, and in this respect gimmers tend to fall between hoggs and ewes.

(iv) Weather conditions may have an influence on the height and duration of the spring peak of worm egg production.

A D-D mixture was tested against the Root-Knot Eelworm, Heterodera marioni (Cornu), in a glasshouse devoted to the growing of tomatoes under commercial conditions in South Wales. The effects of four different rates of application, namely, 0, 200, 300 and 400 lb. per acre injected at a depth of seven inches at staggered points fifteen inches apart were investigated.

Improvements in growth of the tomatoes and reductions in the eelworm manifestations on the roots were produced in proportion to the increases in the dosage rate. Height of the plants, number of flower trusses and yield of fruit were selected for actual measurements of the effects produced on the growth of the tomato plant. All of them showed a graduated response to the injections at 200, 800 and 400 lb. per acre, the yields of marketable tomatoes, for example, being at the three dosage levels, respectively, about 200, 850 and 450 per cent. higher than in the controls.

The nematocidal effects were measured independently by grading the roots into four distinct categories, according to the severity of the pathological manifestations associated with the presence of Heterodera marioni. Judging by the results obtained in this way, D-D reduced the infestation by something like 25, 50 and 75 per cent, when injected at the rate of 200, 800 and 400 lb. per acre respectively. No information regarding the quantity necessary to effect complete extermination is available but it seems that an application exceeding 400 lb. would be imperative for this purpose at least in heavily infected soils where 70 per cent, of the plants are liable to suffer severe infestations.

Tests have been made with methyl bromide to investigate its efficiency in destroying infective stages of some helminth and protozoan parasites of poultry and game birds. It appears to have an immediate strong lethal action against ova of the common nematode parasites and against oocysts of Eimeria tenella. Its efficiency against ova of Choanotaenia infundibulum was not definitely proved. When used in the field, it penetrates soil to a depth of several inches, and in so doing destroys both ova and many invertebrates known to be vectors of poultry parasites. Land which has been treated remained quite free from parasitic infection for many months but gradually became re-infested. Wild birds were probably the agents for they carry ova accidentally on their feet and in the gut.

It is well known that certain weeds can act as alternative hosts for some races of stem eelworm, thereby tending to defeat the objects of crop rotation. During the course of advisory work in this province, collections of weeds have been made from various sites where stem eelworm attacks were known to have occurred, with a view to discovering which ones were likely to act as bridging hosts.

While it is fully realised that the presence of D. dipsaci in a weed growing amongst a crop infested with this eelworm does not prove that the eelworms are of the same biologic race, it is felt that observations of this kind are a valuable and necessary preliminary to host transference experiments.