president’s address. 
11 
The diplococcus of Croupous Pneumonia was discovered by 
Friedlander, and is often called the Micrococcus of Pneumonia, or, 
more shortly, Pneumococcus. In the last year or two another 
diplococcus has been observed by Fraenkel in the expectoration of 
pneumonic patients, which he and some others consider the specific 
cause of the malady. In England Friedlander’s diplococcus still 
holds its ground, but on the Continent that of Fraenkel is beginning 
to find more favour in the eyes of bacteriologists. The diplococcus 
pneumoniae of Friodliindor can be cultivated outside the body. 
As the disease does not generally show itself infectious, the micro- 
organism is clearly saprophytic. Every now and then, however, 
pneumonia appears endemic in certain localities, whereby its 
infectious character is clearly demonstrated. 
The micrococcus of Gonorrhcea, called also Gonococcus, is an 
obligato parasitic microbe, and cannot exist for an indefinite period 
of time outside the body, although it may be readily cultivated in 
nutrient media. It does not seem a very unreasonable expectation 
that this formidable microbe might entirely be banished from 
our globe, if popular governments wero not so excessively 
sentimental. 
Staphylococcus pyogene s and Streptococcus pyogenes are very 
intimately connected with suppuration or the formation of pus. 
When a wound heals badly, they are generally the cause of the 
mischief. When a patient, after an operation, is attacked with 
that terrible malady Pyaemia, one or other of these microbes lias 
almost certainly found its way into his system. Being saprophytic, 
and apparently omnipresent, mankind are ever liable to their 
attacks. The immense progress which surgery has made during 
the last decade or two is mainly due to the rigid exclusion of these 
two microbes from operation wounds. Operations that in my 
student days were almost invariably fatal, however skilfully 
performed, are now carried out with comparative impunity by 
a vast number of surgeons. The pyogenic streptococcus and 
staphylococcus can both be artificially cultivated outside the body, 
and always set up suppuration when inoculated into living animal 
tissues. 
