ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
295 
and a few linin strands which run from the karyosome through the 
layer of peripheral granules to the nuclear membrane. The peripheral 
granules show a different staining reaction from the karyosome. Tiie 
nucleus of the cysts contains the same structures as that of the motile 
amoeba. The karyosome, however, becomes eccentrically placed, and 
the peripheral granules, which vary greatly in number among different 
nuclei, become localized on one side of the karyosome, between it and 
the nuclear membrane. The structure of the nucleus of the amoeba of 
the “ iodine cysts ” makes it impossible to identify this form with 
Endolimcix nana or to include it in that genus. J. A. T. 
New Species of Valkampfia. — A. Ch. Hollande ( Arch . ZooL 
Exper ., 1921, 60, Notes et Revue, 33-42, 9 figs.). Description of 
V. crucAat'i sp. n. from the must of white wine. Among the generic 
characters may be noted the large karyosome sometimes with a centriole, 
the distribution on the nuclear membrane of fine granulations of meta- 
chromatin slightly siderophilous, the nuclear division after the premitotic 
plan, and the presence of uninucleate cysts. The new species is marked 
by the .character of the cyst membrane — e.g. resistant to acids and 
bearing a cruciate mark. It develops well in an atmosphere of carbon 
dioxide. The only mode of multiplication observed was by the division 
of small amoebae. It feeds on yeasts and on its neighbours. In contact 
with 3 to 4 p.c. solution of sodium chloride, the amoeba ceases to form 
a cyst, and this “ acquired character ” may persist for several genera- 
tions. J. A. T. 
Food Reactions of AmGsba proteus. — W. A. Kepner and W. Carl 
Whitlock ( Journ . Exper. ZooL, 1921, 32. 397-412, 6 pis.). There 
are two general types of reaction to food : (a) when no contingency of 
escape is presented by the prey, the amoeba tightly surrounds the food ; 
(b) when such contingency is presented, a wide embrace is made and 
the prey is disturbed only when retreat is cut off. These two types of 
food reaction are not fixed, but vary greatly. In reacting to an object 
that usually moves in a horizontal plane, the amoeba surrounds the prey 
in this plane first, and next cuts off its vertical paths of escape. A 
reaction is usually brought about through the co-operation of both 
ectoplasm and endoplasm, though the ectoplasm alone may carry out a 
reaction of the second type. Both the ectoplasm and the endoplasm are 
highly contractile when conditions demand it. The cutting of an 
animal like Paramoecium, into two is primarily a physical and not a 
chemical process — digestion setting in after the prey has been “ defrag- 
mented.” The process of ingesting food is a reversible one. Food 
half, almost, or wholly ingested may be egested. An amoeba’s reactions 
differ from physical and chemical phenomena in that they are qualita- 
tive rather than quantitative, and are made in the interests of the 
acting organism. J. A. T. 
Foraminifera from Nigerian Eocene Clay. — E. Heron-x\llen and 
A. Earland ( Bulletin Geol. Survey Nigeria, 1922, 3, 138-48, 1 pi.). 
A preliminary account of a sma 1 sample of clay from South Nigeria, 
collected by Sir Frederick Lugard. The sample furnished a few very 
distinctive and interesting forms, one of which, at least, Virgulina 
