1. Observations carried out on four groups of sheep during the spring of 1954 are described.

2. A spring-rise in the worm-egg output was found to occur in all the groups studied.

3. The management of the animals precluded rcinfestation during the spring and, in two instances, from 8th January and 22nd, respectively.

4. Time of lambing and nutritional level appeared to influence the onset and magnitude of the spring increase.

1. A method of management of sheep at pasture is described which appeared successful in preventing reinfection by nematodes parasitic in the alimentary tract, with the exception of Strongyloides papillostts.

2. A significant depression of liveweight gain was observed, due to a sub-clinical infestation in lambs at pasture.

3. Reseeded pasture sown on land that had carried sheep 11 months before appeared to be worm-free.

In July, 1952, carrots growing in the Chatteris area of the Isle of Ely were found to be attacked by Ditylenchus dipsaci. The preceding crop had been wheat and for the previous twenty years the crop rotation of the field had been carrots, potatoes and wheat with an occasional crop of celery. There have been two previous records of stem eelworm attack on carrots in this country, both from the Chatteris area, the first in 1981 and the second in 1941.

1. The method of maintaining schistosomes in vitro is described in detail.

2. Observations made on cultured S. mansoni are given.

3. Investigation of glycogen content shows that there is no significant difference between the reserve of glycogen in fresh and cultured worms. It is suggested that the worms do not rely on their reserve of glycogen but can take up carbohydrate from the medium.

4. The method could be adapted for the culture of other helminths besides schistosomes.

The present paper is a report on a collection of helminths collected from gazelles from Tanganyika Territory. It comprises one species of trematode, Paramphistomum microbothriwn; one species of a larval cestodc Taenia hydatigcna; eleven species of nematodes, Trichuris spiricollis; Haemonchus contortus; Trichostrongylus probolurus; Gazellofilaria tanganyikae; Cooperioides antidorca; Paracooperia serrata; P. daubneyi; Longistrongylus meyeri; Impalaia nudicollis; Gazellostrongylus lerouxi gen. et sp. nov. (Trichostrongylidae) and Protostrongylns gazellae sp. nov. The seven last mentioned species are all new records for the gazelle.