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point of view which is distinctly bad for all concerned. Moreover the opportunity for checking the correct working of biological reagents by observation of patients and the clinical course of cases is impossible. I have had occasion to deplore this many times and it is a distinct handicap. It is to be hoped that the incorporation of a new Institute in the immediate vicinity of one of the hospitals will be seriously considered in the near future.
It is a pleasure to be able to record the efficient and loyal cooperation of the staff of the Institute. The high standard of scientific technique attained by them is a matter for congratulation and pride.
A. PROTOZOOLOGY AND HELMINTHOLOGY.
(1) Blood films for Malaria.-Eight hundred and ninety-seven films were examined for the presence of malarial parasites.
The relatively high proportion of malignant tertian infections is again worthy of remark, being almost double the number of the benign type. The unclassified group consists of cases in which parasites were found in the thick drop but not in the thin film and cases in which the thin film was so badly prepared that type diagnosis was impossible.
A careful watch has been kept in order to detect any parasites conforming to the type described by Stephens and named Plasmodium ovale; so far this has been without success.
A new method of staining has been used which appears to give slightly better results than either Giemsa or Leishman used alone. It consists essentially of adding a few drops of undiluted Giemsa stain to the film immediately after the addition of distilled water to the Leishman stain. The result is a considerably sharpened Leishman picture. The exact amount of Giemsa to be used must be determined experimentally for the particular stain, as the limit consistent with a good result is rather narrow.
The value of the thick drop in demonstrating the presence of malarial parasites deserves emphasis. Many seem still to be unaware of the immense advantage offered by this procedure, and consequently it is not uncommon to receive only a thin film to be examined for parasites. The numerous occasions on which the thick drop shows parasites in every field and the thin film fails to show any (or at most one or two on prolonged search) is remarkable. One is forced to the obvious conclusion that a negative report on thin film is no guarantee that the patient is free of parasites, while on the other hand even a short examination of a thick drop will enable a report to be given which has the strongest evidential value.