INTESTINAL TUYPANOPLASMAS OP PISHES. 
183 
with part of the klnetonucleas, which is apparently just 
breaking through (PI. 9, fig. 10). In a still later stage 
(P). 9, fig. 11), the animal has become distinctly pear-shaped, 
and the kinetonuclei lie so that their longitudinal axes are 
almost at right angles to each other. The ti’ophonucleus 
spindle during the later stages of division becomes much 
elongated, and, as is shown in Text-fig. 2, apparently persists 
right up to the very last stage of division. 
As regards the distribution of the parasite, as far as I can 
discover it is limited in its active form to the stomach. The 
Text-fig. 2. 
Last stage of division in Heteromita dahlii. Comp. oc. 12 -f 1'5 
mm. apo. Ki. Kinetonncleus. Tr.sp. Troplionuclear spindle. 
stomachs of the Cyclopterus which I examined give a slightly 
acid reaction with neutral red. According to Biedermann in 
Wintersteiii’s ' Handbuch der Vergleichenden Pliysiologie,' 
Bd. ii, Jena, 1911, van Herwerden found in Cyclopterus 
lumpus that ‘MO c.cm. des filtrierten Magensaftes vom 
erstgenannten Fische wurden schon neutralisiert von 0'4 c.cm. 
n/10 NaOH, woraus sich eine Aciditat von nur 0*014 Proz. 
(als HCl) berechnet.^^ 
In order to examine as far as possible the effect on the 
flagellates of the passage from the stomach into the intestine 
of its host, I mounted a live smear of the parasite in intestinal 
juice. The parasites seemed at first to become swollen and 
revolve round and round instead of exhibiting 'their usual 
normal progressive mov^ement. Ten minutes after mounting 
