Cockroaches [presumably _Blatta orientalis_, _Blattella germanica_ and/or _Periplaneta americana_], Egypt (El-Kholy and Gohar, 1945): From suspensions of macerated whole insects. =Alcaligenes recti= (Ford) Bergey et al. _Synonymy._--_B. alcaligenes recti._ _Habitat._--Intestinal canal. _Natural vectors._--_Blatta orientalis_, Poland (Nicewicz et al., 1946): Isolated from intestinal tract. =Alcaligenes viscosus= (Weldin and Levine) Weldin _Habitat._--Water, dairy utensils; produces ropiness in milk. _Natural vectors._--_Blattella germanica_, U.S.A. (Janssen and Wedberg, 1952): Isolated from intestine and feces. Family ENTEROBACTERIACEAE =Aerobacter aerogenes= (Kruse) Beijerinck _Synonymy._--_Bacillus lactis aerogenes._ _Habitat._--Grains, plants, intestinal tract of man and other animals. _Natural vectors._--_Blaberus craniifer_, U.S.A. (Wedberg et al., 1949): Isolated from feces. _Blatta orientalis_, Poland (Nicewicz et al., 1946): Isolated from intestinal tract. _Blattella germanica_, on shipboard (Morrell, 1911): Isolated from feces. _Periplaneta americana_, U.S.A. (Bitter and Williams, 1949): Isolated from intestinal tract. Cockroaches [presumably _Blatta orientalis_, _Blattella germanica_ and/or _Periplaneta americana_], Egypt (El-Kholy and Gohar, 1945): Isolated from outer surface of body, intestinal tract, and suspensions of macerated whole insects. =Aerobacter cloacae= (Jordan) Bergey et al. _Synonymy._--_Bacillus cloacae._ _Habitat._--Sewage, soil, water, human and other animal feces. _Natural vectors._--_Blattella germanica_, on shipboard (Morrell, 1911): From feces. U.S.A. (Janssen and Wedberg, 1952; Steinhaus, 1941): From intestinal tract, feces, and oötheca. _Periplaneta americana_, U.S.A. (Bitter and Williams, 1949): From intestinal tract. =Aerobacter= sp. _Natural vectors._--_Periplaneta americana_, U.S.A. (Bitter and Williams, 1949): Isolated from intestines. [cross] =Eberthella oedematiens= Assis _Habitat._--Intestinal canal. _Natural vectors._--_Periplaneta americana_, U.S.A. (Bitter and Williams, 1949): Intestinal tract. * =Escherichia coli= (Migula) Castellani and Chalmers _Natural vectors._--_Blatta orientalis_, Italy (Cao 1898, 1906; Spinelli and Reitano, 1932); France (Sartory and Clerc, 1908); Europe (Jettmar, 1935); Poland (Nicewicz et al., 1946). _Blattella germanica_, U.S.A. (Steinhaus, 1941). _Periplaneta americana_, U.S.A. (Bitter and Williams, 1949, 1949a). Cockroaches [presumably one or all of the above three species], Egypt (El-Kholy and Gohar, 1945). Cockroaches, U.S.A. (Longfellow, 1913). _Experimental vectors._--_Blattella germanica_, Germany (Vollbrechtshausen, 1953): When injected anally or orally the bacteria invaded the intestinal cells and in heavy infections killed the cockroaches. =Escherichia coli= var. =acidilactici= (Topley and Wilson) Yale _Synonymy._--_Bacillus acidi lactici._ _Source._--Diseased nun moth larvae.