392 ALDO CASTELLANI AND ARTHUR WILLEY. 
its endoglobular phase offers few characters of distinction. 
In snakes of this and other species obtained in places remote 
from Colombo we have searched in vain for Hematozoa, 
although Entozoa are common in all parts of the country. 
A young snake of the above-named species, upwards of 
two feet long, was found to be infected with an endoglobular 
hemogregarine of the usual type, all the trophozoites being 
approximately at the same stage of growth, more or less bent 
into a U shape. They show slight differences from Hemo- 
gregarina nicorie. ‘Their size is larger, 12 microns or 
‘012 mm. in length, the protoplasm stains uniform blue, the 
reddish-blue stained nucleus is denser, and placed near the 
pole opposite to the bent portion. The greater density of 
the nucleus ‘is evidenced, not only by the closer aggregation 
of its chromatin material, but also by a greater resistance 
to the staining reagent; in many instances it has remained 
unstained. If the parasite is artificially liberated from the 
blood-corpuscle on the slide, its nucleus becomes well stained. 
The parasites were kept fresh under observation in a 
hanging drop for several days, but no change was observed 
to take place. 
It is not known what stimulus provokes the endoglobular 
hemogregarines to enter upon a new course of development, 
and it appears that they may live for several months without 
undergoing much appreciable change within the blood-cells 
of their host. 
It seems clear, however, that a point is reached eventually 
when something must happen, and a great change take place 
analogous to the change which Schaudinn had described in 
the life-history of Halteridium. 
A few days after making the observations described above 
we were able to examine the blood of a large snake of the 
same species, nearly four feet in length. This examination 
revealed the presence of great numbers of hemogregarines 
free in the blood-plasma in which they performed active 
movements, displacing the corpuscles as they glided along. 
Several hanging drops were prepared as usual, but on the 
