THE MOKADS. 
13 
germs. It h;is been found 
that while a fully grown mon- 
ad, cMed BalUngejna, maybe 
destroyed at a temperature of 
142'' P., the germs or young, 
which are inconceivably mi- 
nute,requiringtobe magnified 
3000 diameters in order to be 
seen, perish only when heated 
in fluid to from 212° F. to 
268° F. It would thus appear 
that no living beings, either 
plant or animal, are excep- 
tions to the universal law that 
all arise from germs. Hence 
the doctrine of .spontaneous 
generation, which implies 
that the lower animals may at 
the present day develop spon- 
taneously by chemi CO -physical 
action, is not true. 
Some monads are phospho- 
rescent. Such is the gigantic 
monad called Noctiluca (Fig. 
9), which occurs in great num- 
Fio. 9.— Noctiluca miUaris, diameter 14 
to 1™™, and its germs or zoospores, s, 
style ; n . nucleus. Greatly magnified. 
Fig. 10.— Paramecium caudatum. A 
view from the dorsal side, magnified 
340 diameters. H, the head; T, the 
tail; m, the mouth; m to g, the 
throat ; a, the posterior opening of 
the digestive cavity; cv^ , the anterior 
and cv posterior contractile vesi- 
cles; I, II, III, the radiating canals 
of cv^; n, the reproductive organs; 
V, the large vibrating cilia at the 
edge of the vestibule. 
