Although within the last few years—chiefly owing to the diagnostic ability and brilliant technical skill of Professor Robert Newstead, F.R.S.—several additions have been made to the list of recognised species of Glossina, the numerical total of which now stands at nineteen, the Glossina morsitans Group has not received a single accession. Peculiar interest therefore attaches to the discovery of the species described below, not only by reason of its apparent pathogenic importance,* but also on account of its systematic position within the genus.