1. In monkeys experimentally infected with B. Mansoni and B. ? bovis the positive signs of infection appear in the following order and intervals after exposure respectively - complement fixation 3 weeks, eosinophilia 6 weeks, and ova in faeces 8 weeks. 2. The complement fixation test remains positive throughout infection (longest period 9 months). The eosinophil count shows a steep rise starting after about 6 weeks and reaching its maximum by the end of the 8th week. Thereafter it falls rapidly until by the end of the 12th week it has returned to normal or near normal. 3. Monkeys infected with cercariae derived from a single miracidium behave exactly as do those with bisexual infections. Thus eosinophilia may result from infestation in the absence of eggs. 4. Of 31 monkeys 2 showed no eosinophilia during 3 months' observation and in 3 human cases only one developed an eosinophilia; therefore eosinophilia is not constantly present in the early stages of bilharziasis. 5. In 3 human cases in which the date of infection was accurately known the sequence of events with regard to the complement fixation and eosinophilia exactly paralleled the work with monkeys. 6. Skin reactions did not occur in our monkeys but in the 3 human cases the first positive reaction-a doubtful one-appeared in the 5th week after infection. 7. It is concluded that under experimental conditions the first and most reliable sign of bilharziasis is a positive complement fixation which functions both in unisexual and bisexual infections.
I. Eight cases of peptic oesophagitis and peptic ulceration in the oesophagus are reported. 2. The aetiology of peptic oesophagitis and the possible mechanisms in its development are considered. 3. The clinical features of peptic oesophagitis and peptic ulcer of the oesophagus are discussed. 4. The radiological features are descriptionbed and the possible relationship of tertiary spasm to peptic oesophagitis is considered. 5. The radiological differential diagnosis of peptic oesophagitis is indicated.