Il8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I4I 



Periplaneta americana, U.S.A. (Gier, 1947; Steinhaus, 1959). 



Periplaneta australasiae and Periplaneta brunnea (Roth and Willis, 

 unpublished data [1954] ) : In laboratory colonies. Isolated from sus- 

 pensions of ground insects. In 1954 we received a culture of Peri- 

 planeta brunnea from the Department of Public Health, University of 

 Minnesota. These insects began to die off rapidly and the normally 

 lightly pigmented parts of the body became red. Dr. Hillel Levinson, 

 Quartermaster bacteriologist, cultured Serratia marcescens from sev- 

 eral moribund individuals. The Department of Public Health of Min- 

 nesota had at times in the past cultured S. marcescens but had dis- 

 carded the cultures and was unaware that it might be surviving in the 

 cockroach colonies (Richards, personal communication, 1954). 



Periplaneta sp., U.S.A. (Olson in Roth and Willis, 1957a) : Iso- 

 lated from an undetermined species of Periplaneta, received in a 

 shipment from the South, a strain of 5". marcescens which was toxic 

 to mice when administered intraperitoneally. 



Experimental hosts. — Blaberus craniifer, U.S.A. (Wedberg et al., 

 1949) : When fed in small numbers, 6". marcescens increased to such 

 an extent that the insect's extremities and upper halves of their bodies 

 turned deep red. The insects died after this color appeared and prac- 

 tically pure cultures of Serratia were recovered from the reddened 

 areas. 



Blatta orientalis, Italy (Cao, 1898) : Isolated from intestinal con- 

 tents. Passed unchanged through the gut. 



Blattella germanica, Canada (Heimpel and West, 1959) : Not nor- 

 mally pathogenic per os; LD50 by injection, is approximately 38,000 

 bacteria per insect. 



Periplaneta americana, U.S.A. (Gier, 1947) : Organism toxic to 

 the cockroach when injected. 



Cockroaches, U.S.A. (Longfellow, 1913) : Isolated from legs and 

 viscera after feeding experiments. 



* Shigella alkalescens (Andrewes) Weldin 

 Natural vectors. — Periplaneta americana, U.S.A. (Bitter and Wil- 

 liams, 1949, 1949a). 



♦Shigella dysenteriae (Shiga) Castellani and Chalmers 

 Experimental vectors. — Blatta orientalis, Italy (Spinelli and Rei- 



tano, 1932). 



Periplaneta americana, Formosa (Morischita and Tsuchimochi, 



1926). 

 Polyphaga saussurei, U.S.S.R. (Zmeev in Pavlovskii, 1948). 



