326 PATHOGENIC MICROCOCCI NOT HERETOFORE DESCRIBED. 



43. STREPTOCOCCUS PERNICIOSUS PSITTACORUM. 



Micrococcus of gray parrot disease. Eberth and Wolff have described 

 an infectious disease of gray parrots, which is said to be extremely fatal 

 among the imported birds. The disease is characterized by the formation of 

 nodules upon the surface and in the interior of various organs, and especially 

 in the liver. Micrococci of medium size are found in these nodules and in 

 blood from the heart ; these are sometimes in chains. Microscopic examina- 

 tion of stained sections shows that these cocci are directly related to the tis- 

 sue necrosis which characterizes the disease. But the micrococcus has not 

 been cultivated and its biological characters are undetermined. 



44. MICROCOCCUS OF FORBES. 



Forbes (1886) has studied an infectious disease of cabbage caterpillars 

 (Pieris rapae), which appears to be due to a micrococcus found by him in 

 large numbers in the bodies of the infected larvae. This micrococcus, which 

 resembles the common staphylococci in form, was cultivated in liquid media 

 and successful inoculation experiments were made. 



