46 
Blood Parasites 
macro- or inicrogamete stage of an ordinary leucocytozoon by the 
presence of numerous red bodies, obviously chromatin, and also by the 
presence of oval or circular vacuoles representing apparently places 
previously occupied by a nuclear body. (Plate III, figs. 37, 39, 40, 
41, 42.) 
Lastly I came across a few multi-nucleated leucocytozoa around 
which were the I’emnants of the nucleus of the host cell. 
One could therefore, I thiuk almost definitely, say that the large 
blue free bodies with numerous nuclei met with in very small numbers 
in the peripheral blood, more numerous in the heart blood and con¬ 
siderably more frequently in the blood from the lung, were originally 
occupants of the protoplasm of the leucocytes, just as the leucocytozoa 
are, and there can be little doubt that they represent a multiplying 
phase of the leucocytozoon of the thrush which probably takes place in 
the lung. 
It is rather remarkable that although I have examined, during the 
last ten years, the blood of a very large number of thrushes and 
blackbirds (I have especially confined my attention to these as they are 
easily procured) I have never met with analogous structures in the 
blood from the peripheral vessels or heart. I have unfortunately not 
examined the blood from the lungs, spleen, or bone marrow, nearly as 
frequently. 
Proteosoma of Birds. 
I regard this as an extremely rare infectiorr of birds in this locality, 
and have only met with these intracorpuscular parasites in three thrushes 
and in one blackbird. In two of the thrushes the Proteosoma were 
exceedingly scanty and they were associated with Leucocytozoa and 
micro-filariae. In one thrush they were very numerous and were found 
associated with halteridia, leucocytozoa, trypanosomes and micro-filariae. 
In the blackbird the Proteosoma were extremely infrequent and were 
associated with Halteridia. 
I have been able to follow in the thrush all stages in the develop¬ 
ment of this parasite, but did not manage to make permanent 
preparations of the flagellating forms. 
Spirochaetes in the Bat. Spirochaeta vesperuginis sp. n. ? 
The blood of 20 Pipistrelles, the common small bat, 3 Noctules or large 
short-eared bats and 2 large long-eared bats was examined and I found 
spirochaetes in one Pipistrelle ( Vesperugo pipistrellus), and in one 
Noctule {Vesperugo noctula), both of which were sent from Reading. 
