AND OF EXPOSED MUCOUS MEMBRANES. 651 
variety of bacteria; among others the pus cocci were frequently 
found by both of the observers mentioned. In eighty one cases Von 
Besser found the “diplococcus pneumoniz” fourteen times, Staphy- 
lococcus pyogenes aureus fourteen times, Streptococcus pyogenes 
seven times, and Friedlander’s bacillus twice. Twenty-eight of the 
cases examined were convalescents in hospital; among these the 
pathogenic species mentioned were found less frequently than in other 
individuals. The following non-pathogenic species were isolated: 
Micrococcus liquefaciens albus in twenty-two cases, Micrococcus al- 
bus in nine cases, Micrococcus cumulatus tenuis in fourteen cases, 
Micrococcus flavus liquefaciens in three cases, Bacillus striatus albus 
in ten cases, ete. 
Paulsen (1890) made thirty-one cultures in nutrient gelatin from 
sixteen persons and thirty-three in nutrient agar from twenty-two 
persons, with the following result: Eleven remained sterile, nineteen 
showed not more than ten colonies, sixteen less than one hundred, 
twelve more than one hundred, and in six the number was so great 
that they could not be counted. Micrococci were more numerous 
than bacilli; of these a “sulphur-yellow coccus” in tetrads was found 
in eight individuals. Various species of liquefying cocci, resem- 
bling the pus cocci, were isolated, but the conclusion was reached 
that none of these were identical with the staphylococci of pus, 
which Von Besser and Wright both found in a considerable propor- 
tion of the culture experiments made by them. 
Thomson and Hewlett (1895) have recently reported results which 
differ to some extent from those previously reported. While they 
found numerous bacteria in the vestibulum naris, cultures made from . 
mucus obtained from the interior of the nose usually gave a negative 
result—sixty-four out of seventy-six remained absolutely sterile, 
while in seven there was a scanty growth only. They conclude that 
while microédrganisms are occasionally found upon the Schneider- 
ian membrane they are not numerous and are often entirely absent; 
and that they are rarely found upon the pituitary membrane. Straus 
(1895) has examined the nasal secretions of persons associated with 
tubercular patients for the purpose of ascertaining if the tubercle ba- 
cillus was present. The presence of this bacillus was demonstrated, 
by inoculation into guinea-pigs, in nine healthy individuals out of 
twenty-nine examined; two of these were physicians and six were 
nurses. 
Very extended researches have been made with reference to the 
bacteria present in the human mouth, which show that numerous 
species are constantly present in the buccal secretions and upon the 
surface of the moist mucous membrane. Some of these are occa- 
sional and accidental, while others appear to have their normal habi- 
