ON THE TRYPANOSOME OF THE LITTLE OWL. 
1 55 
March 27 tli-2 8th, midnight : Leucocytozoon not at all 
frequent, rather scanty in fact, requiring considerable search- 
ing. Parasites distinctly in batches. In one drop none were 
seen after much searching, while in another four or five 
intra-cellular forms were come across one after another 
fairly quickly. In a drop diluted with salt-citrate solution 
two ripe females and also two flagellating males were 
found. 
March 30th, morning : Leu cocy tozoon numerous. Many 
rounded-off females observed, but only one flagellating 
male. 
April 3rd, afternoon: Owl 11 died. Leucocy tozoon 
numerous, both in blood and internal organs. No rounded- 
off or flagellating individuals were observed, however, whether 
in preparations to which salt-citrate had been added or in 
those to which it had not been. 
In several ot‘ our other owls in which Leucocy to zoon 
was present (e.g. Nos. 14, 17 and 19), the parasites were 
infrequent or scarce whenever the birds were examined (this 
being the case even in the internal organs after death), and 
consequently no such variation in number was observed. In 
owl 22, however, which had a very good infection with Leu- 
cocy to zoon, the above phenomenon was again noticed. 
June 13tli, morning after arrival : Leucocytozoon 
numerous ; many flagellating as well as rounded-off individuals 
seen. 
June 21st— 22nd, midnight : Parasites not nearly so 
numerous, only fairly frequent, and no flagellating or 
rounded-off individuals were observed. 
June 22nd, afternoon : Owl 22 died. Both in the heart- 
blood and in the bone-marrow Leucocytozoon was fairly 
numerous, distinctly more frequent than in the peripheral 
blood the night before, but again no ripe forms were seen — 
either rounded-off or flagellating. 
Of our birds infected with Leucocy tozoon, the one which 
we had under observation for the longest period was No. 14, 
which was first examined on April 20th and lived till May 
VOL. 57, PART 2. NEW SERIES. 13 
