CONJUNCTIVA IN HEALTH AND DISEASE 107 
No. 3 in Table III was a slender spore bearing bacillus corresponding to the 
description of the bacillus of Colomiatti ; morphologically it resembles B. alvei, 
which was found on one occasion by Eyre in the normal conjunctival sac. The 
bacillus occurred in muco-purulent catarrh, but for convenience of description I have 
included it in the description of organisms obtained from healthy eyes. 
Many varieties of bacilli resembling in some particular the B. diphtheriae 
have been isolated from the conjunctiva, and forms varying from a short regular 
bacillus not forming typical involution forms and a form indistinguishable from the 
diphtheria bacillus in all its reactions have been obtained. 
A table (IV) has been drawn up describing the cultural peculiarities of a few 
of those bacilli which have features sufficiently different to distinguish them from 
other members of the group. In this table, for convenience of description and 
comparison, has been included two varieties (4 and 5) only noticed in pathological 
conditions. 
The organism known as the xerosis bacillus is the most common inhabitant 
o 
of the conjunctival sac. 
In two hundred and ten examinations it was found one hundred and twenty 
times, and it is not improbable that by using a larger amount of fluid it might 
have been found in a great many of the remaining cases. 
In frequent instances so enormous must have been the number of organisms 
in the conjunctival sac, one loopful of fluid produced on the surface of the serum 
over two hundred colonies of this bacillus in pure culture. It was very common to 
produce from thirty to one hundred colonies in one inoculation. 
To determine the time taken for colonies of xerosis bacillus to become visible 
to the naked eye, tubes were examined at different periods of incubation. On repeated 
occasions minute transparent colonies have been observed at the end of sixteen to 
eighteen hours, which have subsequently been proved to be the bacillus under 
consideration. 
In morphological appearance the xerosis bacillus is very similar to the 
diphtheria bacillus, but differs from it in cultures. On serum the colonies are small, 
greyish-white, and very adherent to the surface of the medium ; colonies of the 
diphtheria bacillus in the same time are much larger, whiter, and softer. On agar 
the xerosis colonies are very small, greyish, and translucent, and on media containing 
glucose growth is not accompanied by the formation of acid. 
No. 2 (table IV) died out before a complete study had been made of its life 
history ; it somewhat resembled a bacillus (diphtheroid I) isolated by Eyre 1 from milk. 
No. 3 I have taken to be Hoffman's bacillus ; it was identical in every 
respect with a Hoffman's bacillus derived from the throat. 
I. On the presence of members of the diphtheria group of bacilli other than the Klebs-h'iffer bacillus in milk. British Medical 
Journal, August 18, 1900. 
