138 THOMPSON YATES LABORATORIES REPORT 
With scarcely one exception the disease in Table III was of considerable 
duration ; most of the patients could give no definite history, with the exception that 
they had had ' sore eyes ' since childhood. It would, therefore, not be expected that 
in such a series uniformity in the incidence of a specific organism would be secured, 
and in the consideration of the agents causing trachoma this table has not been taken 
into account. 
The pyogenic cocci were of frequent occurrence ; staphylococcus aureus was 
found five times ; staphylococcus citreus, three times ; staphylococcus albus, once ; 
streptococcus longus, three times ; pneumococcus, once. 
B. lacunatus (Eyre) was isolated on three occasions, once associated with 
Fraenkel's pneumococcus. On each occasion there was considerable inflammatory 
reaction, and it is probable that the inflammation caused by the bacillus was super- 
added to the granular lids. B. lacunatus rarely causes an acute conjunctivitis, but 
the conditions for its growth are much more favourable in a conjunctiva disorganized 
by granules than in a previously normal one. Xerosis bacillus occurred in every case, 
in some of them in large quantity. 
In two of the cases, 6 and 10, where all sign of granules had disappeared and 
the conjunctiva had undergone natural recovery, xerosis bacillus was obtained in pure 
culture. Staphylococcus aureus was almost invariably found when the conjunctiva 
was thickened and velvetv. 
The almost constant appearance of Koch-Weeks bacillus in the first group, 
makes the conclusion inevitable that this bacillus is very often the cause of an inflam- 
mation of the conjunctiva, accompanied by the formation of granules. It has been 
seen that when these cases have been left untreated for some time the granules grow 
in diameter. Also, not only have cases been observed to develop granular lids from 
simple muco-purulent catarrh, but also several families have come under observation, 
in which the individuals have each suffered from muco-purulent catarrh, or some form 
of granular lids, the cause of the muco-purulent catarrh being in all cases Koch- 
Weeks bacillus. 
These facts are strong evidence that the different varieties of granular lids are 
stages of the same disease, and that in all probability all cases of trachoma have com- 
menced in the formation of the minute miliary granules, as a result of infection by 
Koch-Weeks bacillus. 
The view is now generally accepted that trachoma is a specifically contagious 
disease due to some organism. In epidemics of trachoma in schools, muco-purulent 
catarrh often accompanies and equals trachoma in incidence. 
The failure to find Koch-Weeks bacillus in more than four cases (? two) of 
the second group may be accounted for by the fact that — 
