CONJUNCTIVA IN HEALTH AND DISEASE 125 
Cultural Peculiarities 
The cultivation of the bacillus conjunctivitis was very difficult. It does not 
grow on the ordinary laboratory media, and only occasionally on coagulated horse 
serum. Pure cultures, however, have been obtained on horse serum, serum agar, and 
human blood agar. On the two latter media a few colonies only grew on one 
occasion, and sub-cultures could not be obtained. On serum there was better success, 
and sub-cultures were made to the third and fourth generation. The saprophytic 
growth of the bacillus varies considerably, and seems to depend upon the period it 
has been exposed to the action of the lachrymal secretion. If cases are taken early, a 
good growth can be obtained on serum. In the four acute cases a good growth was 
obtained on serum, and the organism retained its vitality for some time. In muco- 
purulent catarrh of some duration a good growth was most difficult to obtain, and 
sub-cultures were not readily made. 
During the course of these observations, Rein hard Hoffmann, 25 in a paper on 
the Koch-Weeks bacillus, mentions that a medium composed of two parts of two per 
cent, glycerine- peptone agar and one part of human ascites fluid, mixed with sterile 
wether blood in the proportion of one to two, gave very good results, and that he 
was able to sub-cultivate the bacillus up to the twenty-fifth generation. 
So far as my observations with this medium go, I have been unable to confirm 
Hoffmann's statements. 
On serum the colonies are minute, discrete, transparent, slightly raised growths, 
with a rounded conical centre and flat smooth margins. The colonies can only be 
seen with distinctness by the aid of a magnifying lens. In two days they have 
obtained their greatest magnitude. In one case they were found growing in association 
with a coccus, and in several cases they occurred in mixed culture with the xerosis 
bacillus. 
Microscopically, the colonies consist of very slender, non-motile rods, varying 
in length but not in thickness ; some of them grow out into fairly long curved threads. 
Many of the shorter bacilli are divided by a barely perceptible division. Most of the 
bacilli are cylindrical, but a few show slight irregularities of contour, which may be 
evidence of commencing subdivision. No chains or degeneration forms are seen. 
They stain well with fuchsin, but lightly with methylene blue and dahlia ; the 
stain is not retained by Gram's method. They are non-motile. 
Inoculation experiments on rabbits with pure cultures were unsuccessful, but 
with the mixed growth of Koch-Weeks bacillus and coccus a slight catarrh was 
produced, lasting for three days, and manifesting itself chiefly in the discharge of a 
small quantity of white muco-pus. Microscopically, the pus contained numbers of 
Koch-Weeks bacillus. 
The interest of these cases lies in the fact that they may readily be mistaken 
for infection by the gonococcus. Clinically, in the case of the two children it was 
