On the Hæmatozoan Infections of Birds

Our knowledge of the nature of these infections, sometimes loosely designated as avian malaria, is mainly due to the researches of Danil-The only work upon this subject so far done in America was reported in the papers on the etiology and pathology of h~ematozoan infections in American birds, read by Opie and myself before the Medical Society of the Johns Hopkins are published in full in the present number of this Journal (pp. 79 and 103), give the results of observations made at the suggestion of Dr. Thayer of the Johns Hopkins Hospital, in the summer of 1896, on the blood and organs of various birds. During the past summer (1897) I have continued the work in Dunnville, Ontario, confining my attention mainly to crows, which seem to afford the most promising field for observation. Many species of birds have been found to bc infected with these organisms to a greater or less degree-in Europe sparrows, finches, starlings, blackbirds, crows, hawks, etc. In Ontario and Maryland, where we have procured our birds, we have found sparrows, black= birds, owls and crows infected, and of these the crows were most frequently so, for although the number is too small to furnish any definite conclusions as to relative frequency of infection, some idea of this may be gained from the fact that of eighty sparrows the blood of five showed organisms, while of twenty-one crows sixteen were infected. The organisms in these cases are very similar in many respects to those found in the blood of human beings suffering from malaria.