Filariasis in the Middle East.

obtained a considerably higher proportion of men with 0/5-7% in even his best group. This discrepancy is probably mainly due to difference in technique, and emphasizes the advantage of the viewing-screen over goggles. In spite of constant attention the latter become fogged and are a source of error. The chief interest of this series of results is the illustration it gives of the downward trend of scotopic vision which occurs with advancing years. According to these results the drop begins before the age of 18. Since, however, the drop from the average at 18 to that at about 44 is only in the region of 3 ,uml., this point is of theoretical rather than of practical importance. Summary The brightness figures of the Army night-vision test are given, with a qualifying remark on the colour of the light in adaptometers. Though the test is one of form sense it appears that the 'minimnum light necessary for the discrimination of a simple form is in the region of the absolute light threshold. The results are recorded of 10,333 tests, the subjects of which were high-category men between the ages of 18 and 55. They illustrate the downward trend of scotopic vision which occurs with advancing years. It is not unusual to meet with cases of clinical filariasis among African native troops in the Middle East, and one of us (J. F.) has seen them in all three hospitals to which he was temporarily attached. In view of the high incidence of microfilariaemia among natives in certain regions of Africa reported in the literature, it was considered of interest to carry out a routine examination of the blood of all negro patients in the wards of a general hospital, irrespective of the condition for which they were admitted. At the same time information was obtained of the country of origin in each case and the period that had elapsed since they left their homes: in practice this period corresponded to the time of enlistment. The findings are shown in Table I. An inspection of the table revealed that: (1) 12 cases (29%) out of 42 showed the presence of microfilariae; (2) 30 out of the 42 patients came from Uganda, and all the positives were in this group-i.e., Uganda soldiers showed 40% infestation with filaria; (3) of the 12 cases of filariaemia only two had clinical filariasis; (4) the patients with filariaemia …