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776 coiled up under the skin, he injects as near the coils as possible, and through several punctures, a few drops of the same solution. This, too, kills the parasite. Her body is then absorbed, as a piece of aseptic catgut would be, without inflammation or reaction of any description; or she may be cut down on, and easily extracted. Others have confirmed the value of Emily's method, which saves much time and suffering and, with due care, is devoid of risk. Prophylaxis.— From what has been stated with regard to the role of cyclops, it is evident that the prevention of guinea-worm is merely a question of protection of drinking-water from pollution by the subjects of guinea-worm infection. Leiper has shown that by raising by a few degrees the temperature of the water in which cyclops are living these crustaceans are killed. He suggests heating by a portable steam generator the water in wells and water-holes known to be sources of guinea- worm infection, as a prophylactic measure. Alcock has found that the addition of a trace of potash to the water is equally effective.

Synonyms.— Dracunculm oculi; Filaria loa; F. oculi; F. subconjunctivalis; F. diurna; F. bourgi. History.— Loa loa (Fig. 153) has been known for more than three hundred years. Although undoubtedly of African origin, the earlier-described cases were in negroes in the West Indies who must have acquired their parasites in West Africa prior to their deportation as slaves to America. For long the worm was regarded as an immature dracunculus. Since the characters of the parasite have been more carefully studied this view can no longer be held, and L. loa is now thoroughly established as a distinct species. " In 1891 I found in the blood of two negroes— one from the Lower Congo, the other from Old Calabar—certain microfilariæ morphologically closely resembling that of F. bancrofti, but differing from the latter inasmuch as they came into the peripheral circulation during the day and disappeared from it during the night. As in one of these negroes L. loa