In a previous paper (1) we reported the successful inoculation of three patients with two strains of P. malariae by means of infected A. quadrimaculatus. Further propagation of one of these strains was not attempted, but we succeeded in recovering the parasites of the second strain (of the previous report) in quadrimaculatus, with which two of three patients in a second series were successfully inoculated. Since this time we have been obliged to maintain this strain by blood inoculation, as gametocyte production has been too inconstant to justify our attempting its consistent propagation by mosquitoes.
The clinical attack of case 7 of the previous report began on December 23, 1932, and continued until May 21, 1933, when it was interrupted by Sinton's treatment. From the onset to February 12, his paroxysms occurred regularly every fourth day. Beginning on that date, a new series of paroxysms was initiated, anticipating the original cycle so that he experienced a double quartan.