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XLII] somehow produced by L. loa. On the supposition that the swelling might be caused by the emission of her larvae by a parent loa into the connective tissue. I endeavoured in one case, by aspirating the centre of the swelling with a hypodermic syringe, to substantiate this speculation; the result was negative, bub a second attempt on another patient yielded great numbers of microfilariæ in the lymph abstracted. Notwithstanding this success it cannot be affirmed that the mechanism of the production of Calabar swellings has been solved.

Synonym.— Filaria volvulus, Leuck., 1893. History.— Onchocerca volvulus was discovered by a German medical missionary, who noticed peculiar worms in two tumours the size of a pigeon's egg, which he had removed, one from the scalp, the other from the chest of Gold Coast negroes. The tumours were forwarded to Leuck art, who described and named the parasite Filaria volvulus in 1893. In 1899 Labadie-Lagrave and Deguy found an immature female filaria, which Blanchard identified as ''0. volvulus'', in a small tumour removed from the arm of a soldier, who must have contracted the infection six years previously whilst campaigning in Dahomey. Labadie - Lagrave and Deguy were able to show that the parasite occupied a lymphatic vessel. In 1901 Prout described two cases from Sierra Leone. Brumpt, during his travels through Central Africa, had the opportunity of examining numerous cases. Recently Fülleborn, Parsons, and Clapier have added considerably to our knowledge of this parasite. Other species, such as ''0. gibsoni'', are parasitic in cattle and give rise to small nodes in beef. It has been suggested by Cleland that this species is transmitted by Stomoxys.

Geographical distribution.— The earlier cases were reported from the West Coast of Africa —Sierra Leone, Gold Coast, Dahomey. Brumpt met with his cases along the Welle between Dongon and