C. A. Hoare 
77 
from the heart either by means of a sterile pipette or by cutting the main 
artery (Truncus arteriosus) and allowing the blood from it to drop on a slide. 
Then, without injuring the alimentary canal (to avoid mixing its contents 
with other organs) the liver and spleen were removed and smeared on a slide. 
Films of the peritoneal fluid were also made. Lastly, the alimentary canal was 
totally removed and the stomach separated from intestine. The contents of 
the stomach and intestine, as well as the blood and peritoneal exudate, were 
examined both fresh in normal saline and in stained preparations. 
Experiment 16 (VII). Fish fed on September 30th with one gut, October 1st, one gut, 
October 4th with two guts, one after another. Altogether it had four guts. Killed two hours 
after last meal. The insect gut was still undigested and nearly intact. The flagellates were 
quite motile in the stomach, but none were found in the intestine. The heart blood contained 
no flagellates, nor were any forms present in the liver, spleen and peritoneal fluid. 
Experiment 17 (VIII). Fish fed on four guts (as preceding). Killed 3§ hours after last meal. 
The insect gut was only partly digested. Motile flagellates were found in the stomach and a 
few already made their appearance in the intestine. No flagellates were found in the blood, 
peritoneal fluid, liver and spleen. 
Experiment 18 (IX). Fish fed on three guts (as preceding, but only one gut on October 
4th). Killed jive hours after last meal. The insect gut was nearly digested. Few flagellates were 
found motile in the stomach, but none in the intestine. No forms found in the blood, exudate 
or liver and spleen. 
Experiment 19 (IV). Fish fed on 12 guts (Sept. 17th one, Sept. 18th one. Sept. 20th 
two, Sept. 21st, 22nd, 23rd, 24th, 27th, 28th, 29th and 30th per one). Killed jive hours after 
last meal. No visible traces of flagellates were found in the digestive tract, blood, exudate, 
liver and spleen. 
Experiment 20 (III). Fish fed on nine guts (Sept. 17th, 18th, 20th, 21st per two, Sept. 22nd 
one). Killed about jive hours after last meal. In the digestive tract flagellates were found with 
nuclei hardly visible, cytoplasm vacuolised, and shape of the body distorted. Apparently 
being digested. None were found in the blood, exudate and other organs. 
Experiment 21 (XI). Fish fed on one gut (Sept. 6th). Killed 18 hours after meal. No live 
flagellates in fresh stomach contents. After the latter were stained, the flagellates were found 
to be apparently partly digested, their body being swollen, staining deeply and no inner 
structures being visible. There were no visible traces of the flagellates in the intestine. The 
insect gut was already wholly digested at this time. No forms of the flagellate were found in 
the blood, exudate and organs. 
Experiment 22 (X). Fish fed on two guts containing an exceptionally large number of 
herpetomonads. Killed 18 hours after the meal. The insect gut was not yet quite digested and 
the alimentary canal contained some live flagellates, whilst others were found dead. None 
were found in the blood, exudate and organs. 
Experiment 23 (I). Fish fed on ten guts (Sept. 16th two, Sept. 17th four, Sept. 18th, 
20th per two). Killed about 24 hours after last meal. Insect gut wholly digested. No traces of 
flagellates in the digestive tract, blood and organs. 
Experiment 24 (II). Fish fed on ten guts (Sept. 17th one, Sept. 20th two, Sept. 21st 
three. Sept. 22nd, 23rd per two). Results as in preceding. 
Experiment 25 (VI). Fish fed on two guts (Sept. 17th and 18th). Killed about 48 hours 
after last meal. Results as in experiments 23 and 24. 
Experiment 26 (V). Fish fed on seven guts (Sept. 17th, 18th, 20th, 21st, 22nd, 23id, 
24th per one). Killed jive hours after last meal. The insect gut was nearly digested. In the 
