* Shigella alkalescens (Andrewes) Weldin
Natural vectors.—Periplaneta americana, U.S.A. (Bitter and Williams, 1949, 1949a).
* Shigella dysenteriae (Shiga) Castellani and Chalmers
Experimental vectors.—Blatta orientalis, Italy (Spinelli and Reitano, 1932).
Periplaneta americana, Formosa (Morischita and Tsuchimochi, 1926).
Polyphaga saussurei, U.S.S.R. (Zmeev in Pavlovskii, 1948).
* Shigella paradysenteriae (Collins) Weldin
Natural vectors.—Blatta lateralis, Tadzhikistan (Zmeev, 1940).
Experimental vectors.—Periplaneta americana, Gold Coast Colony (Macfie, 1922).