§ 12. oT 
wanting, its function is often performed by the mouth. According to 
Ehrenberg, the Infusoria polygastrica, such as we have just been describ- 
ing, differ from the Infusoria rotatoria, in having a great number of stom- 
achs, which connect by hollow peduncles with the mouth in the division 
Anentera, and with the intestine in that of Enterodela. This organiza- 
tion, which, from its high authority, has generally been admitted by natu- 
ralists, is not, however, met with in any infusorium.” 
The vesicular cavities in the bodies of these animals, and which have 
been regarded by Ehrenberg as stomachal-pouches, never have a hollow 
peduncle, either connecting with the mouth (Aventera) or with the intes- 
tine (Enterodela). Indeed, it is doubtful if a digestive canal can be made 
out in these Infusoria. 
The vesicular, irregular contracting cavities of their body contain a 
clear liquid, evidently the same as that in which they live, which, with the 
Astoma, has been absorbed through the surface of the body. But, with 
those having a mouth and msophagus, it is received through them, and 
taken up by the yielding parenchyma of the body. 
If the methods of feeding of Gleichen and Ehrenberg are employed, 
the colored particles are taken in by a vortical action of the water, caused 
by the cilia surrounding the mouth. This water, with its molecules, accu- 
mulates at the lower portion of the oesophagus, and so distends there the 
parenchyma as to cause the appearance of a vesicle. Thus situated, the 
whole has much the aspect of a pedunculated vesicle. But when, from 
contractions of the cesophagus, this water escapes into the parenchyma, 
it appears there as an unpedunculated globule, in which the colored 
particles still float. When the Stomatoda are full-fed in this manner, there 
appear many of these globules in various parts of the body; and thus sub- 
stances previously ingested are taken up and disseminated throughout the 
body. 
i the globules thus containing solid particles are closely aggregated, it 
sometimes happens that they fuse together; a fact which proves that they 
are not surrounded by a special membrane. 
The solid particles of food of the Stomatoda, which are often the 
lower Algae, such as the Diatomaceze and Oscillatoria,and often other Infu- 
soria, are sometimes deposited in the parenchyma without being surrounded 
by a vesicular liquid.* 
From observations made upon Amada, Arcella and Diffiugia, it appears 
that the Rhizopoda ‘ingest their food like the Stomatode Infusoria, 
INFUSORIA AND RHIZOPODA. 
neck. ( Miiller’s Arch. 1839, p. 80; also Monats- 
bericht der Berliner Akad. 1841, p. 103.) But, de- 
tailed as they may be (see Ehrenberg Abhandl. d. 
Ber. Akad. 1830, Taf. IfI.; 1831, Taf. III.; also “Die 
1 Focke (isis, 1836, p. 785) has already raised 
doubts as to the existence in Infusoria of the 
stomachs described by Ehrenberg. Ehrenberg 
has also opponents in Dujardin (Ann. des Sc. Nat. 
Zool. TV. 1835, p. 364; V. 1836, p. 193; X. 1838, 
p. 280; also Hist. Nat. des Infus. 1841, p. 57), in 
Meyen (Miller’s Arch. 1839, p. 74) and in Ry- 
mer Jones (Ann. of Nat. Hist. ITI. 1839, p. 105 5 
also, “A General Outline of the Animal Kingdom,” 
1841, p. 56). . 
He has attempted to reply to the objections here 
urged by very detailed illustrations of the organ- 
ization of the Polygastrica, made by him and Wer- 
* Bailey (Amer. Jour. Sc. May, 1858, p. 341) 
has recently published an t, panied 
with numerous figures, of a new animalcule, which 
is so remarkable in this connection that I give here 
his description. He says: “If ‘the reader will 
Infusionsthierchen,” Taf. XXXII. XXXVI. and 
XXXIX.), they are not representations of nature. 
The organ whichin Trachelius ovum has been 
taken by Ehrenberg (“Die Infusionsthierchen,” 
p. 828, Taf. XX XIII. fig. xiii. 1) for a branching di- 
gestive tube, has always appeared to me only as a 
solid fibrous cord, traversing the soft parenchyma 
of the body, and by its ramifications presenting a 
coarse meshed aspect, 
imagine a bag made of some soft extensible mate- 
rial, so thin as to be transparent like glass, so soft 
as to yield readily to extension when subjected ta 
internal pressure, and so small as to be microscop- 
ic ; this bag, filled with particles of sand, shells of 
