NO. IO COCKROACHES—ROTH AND WILLIS 57 
Experimental vectors——Cockroaches, U.S.A. (Longfellow, 1913) : 
After feeding, the organism was recovered in a few cases from the 
viscera and outer surface of the body ; however, the results were not 
as conclusive as were Longfellow’s findings with pneumococcus. 
Veillonella parvula (Veillon and Zuber) Prévot 
Synonymy.—Micrococcus parvulus. 
Disease.-—Normally a harmless parasite in natural cavities of man 
and other animals, but it may occasionally be pathogenic. 
Natural vectors.—Periplaneta americana, U.S.A. (Hatcher, 1939) : 
Organism isolated from feces. 
Family LACTOBACTERIACEAE 
Diplococcus pneumoniae Weichselbaum 
Synonymy.—‘‘Diplobacillo di Frankel” of Cao. 
Common name.—Pneumococcus. 
Disease—Commonest cause of lobar pneumonia. Habitat: Re- 
spiratory tract of man and animals. 
Experimental vectors—Blatta orientalis, Italy (Cao, 1898): Or- 
ganism killed in the cockroach’s gut. 
Cockroaches, U.S.A. (Longfellow, 1913): After feeding on the 
organism, 3 out of 10 cockroaches had the bacterium on legs or ab- 
domens. Smears of the opened bodies of all 10 insects showed from a 
few to a number of pneumococcus colonies in each. 
Pneumococcus, Type I, No. 1231 
Disease.—Pathogenic to mice (Vollbrechtshausen, 1953). 
Experimental vectors.—Blattella germanica, Germany (Vollbrechts- 
hausen, 1953) : 25 cockroaches injected orally or anally with pneumo- 
cocci in a serum bouillon. Pneumococci appeared in the feces within 
5 hours after the injection and were excreted over a period of 3 days. 
Experiment repeated with 50 cockroaches. The number of introduced 
pneumococci decreased in the intestines until, after 5 days, the test 
insects no longer showed such bacteria. 
Streptococcus faecalis Andrewes and Horder 
Source.—Occurs in inflammatory exudates; in blood stream in 
subacute endocarditis; European foul-brood of bees. Found in milk 
and milk products, especially cheese. 
Natural vectors—Blatta orientalis, Poland ( Nicewicz et al., 1946) : 
Organism isolated from the alimentary tract. 
