[Electron microscopic studies of Pasteurella multocida bacteriophages].

Studied was the morphology of four Pasteurella multocida phages, Nos. 115, 32, 967, and 1075, with the use of an electron microscope. The bacterial phages had hexagonal heads of a 55 x 55 nm diameter, and were of an isometric polygonal form themselves. The tail of the phages was 120 nm long and was non-contractile. By these characters the P. multocida phages are to be referred to the morphologic group of phages of noncontractile tails--group B after Bradley and group IV after Tihonenko.