No. 376.] REVIEWS OF RECENT LITERATURE. 271 
GENERAL BIOLOGY. 
Studies on Protoplasm.'— The author has here given a summary 
of her studies made during ten years upon protoplasmic phenomena. 
She recognizes that the study of living protoplasm, as opposed to 
preserved and tortured states, may to-day hope for some scattered 
sympathy. Her studies were unhampered by theory or predilection, 
except what may be described as a belief in life genii more complex 
and more potent than even surface tension and osmosis. The author 
has avoided controversial references, although asguing for Biitschli’s 
foam theory of protoplasmic structure. The new facts brought for- 
ward, while not explaining phenomena, serve to unify them. The 
book contains 176 pages. 
It is difficult to summarize this work, but certain main points may 
be noted. Not only is Biitschli’s foam theory accepted, but it is 
extended by supposing, on the evidence of certain appearances which 
are described, that the walls of the alveoli of Bütschli are themselves 
made up of vesicles ; and apparently their walls, in turn, may be vesicu- 
lated, and so on indefinitely. The continuous substance forming 
the walls of the vesicles is the true living matter, the material 
included in its spaces being merely passive. 
The protoplasmic foam is found to have a structure in areas where 
the functions are chiefly vegetative which differs somewhat from the 
structure when the manifestations of contractility and irritability 
predominate. 
The continuous substance is described as being commonly in a 
state of flux, or of active contraction. The spinning out of fine 
filose processes from protoplasmic surfaces was found to be of 
almost universal occurrence and is regarded by the author as of 
fundamental importance. These spinnings may be internal as’ well 
as external to the mass. 
A “new structural formula for protoplasm” is given as follows 
(p. 106): 
“Protoplasm is a very complex emulsion, having the physical 
arrangement of a very finely subdivided, variably viscid foam, 
which characters are coextensive with the continuous element of all 
visible optical reticula.” 
“The substance which at any given moment forms in all sub- 
1 The Living Substance: as Such: and as Organism. By Gwendolen Foulke 
Andrews. ey Ginn & Co., 1897. Supplement to the Journal of Morphology, 
vol. xii, No 
