BIOTIC ASSOCIATIONS OF COCKROACHES — ROTH & WILLIS IO7 



Blatta orientalis, U.S.A. (Tauber, 1940; Tauber and Griffiths, 

 1942). 



Blattella germanica, U.S.A. (Herms and Nelson, 1913; Herms, 

 1939; Janssen and Wedberg, 1952). 



Experimental vectors. — Blatta orientalis, Italy (Cao, 1898) ; U.S.A. 

 (Tauber and Griffiths, 1942). 



Micrococcus pyogenes var. albus ( = Staphylococcus albus) and an 

 unidentified short rod form were found by Tauber (1940) in the 

 hemolymph of B. orientalis. These microorganisms were never found 

 together in the same insect and caused loss of appetite, sluggishness, 

 irregular respiratory movements, and paralysis in the cockroach ; in 

 the final stages of the disease the legs were folded under the body, 

 the head was tucked beneath the forelegs, the whole insect became 

 arched and maintained this position until death. In some cockroaches 

 infected with the rod pathogen, conjunctival folds, particularly those 

 between the dorsal abdominal sclerites, and the joints of the meta- 

 thoracic legs ruptured liberating thick white hemolymph filled with 

 bacteria. Tauber suggested that the infection might be spread by 

 contact, especially to newly molted individuals or by actual ingestion 

 of the bacteria by the cockroaches feeding on dead or dying indi- 

 viduals. All the roaches died after successful inoculation with the 

 Micrococcus. The bacterial infection was associated with high total 

 hemocyte counts and high percentages of mitotically dividing hemo- 

 lymph cells (Tauber, 1940) ; these responses of the insect were in- 

 terpreted as a mechanism whereby the number of hemocytes increases 

 resulting in an increase in the number of phagocytes for combating the 

 bacteria (Tauber and Griffiths, 1942). 



* Micrococcus pyogenes var. aureus (Rosenbach) Zopf 

 Natural vectors. — Blaberus craniifer, U.S.A. (Wedberg et al., 

 1949). 

 Blatta orientalis, Italy (Cao, 1906). 

 Blattella germanica, U.S.A. (Herms, 1939). 

 Cockroaches, U.S.A. (Longfellow, 1913). 



Micrococcus ureae Cohn 



Habitat. — Stale urine and soil containing urine. 

 Natural vectors. — Blattella germanica, U.S.A. (Janssen and Wed- 

 berg, 1952) : From intestinal tract and feces. 



♦Micrococcus spp. 

 These organisms were obtained from pus or were designated as 

 staphylococci [i.e., pathogenic micrococci (Blair in Dubos, 1948)]. 



