74 
and Seifert in the microdissection of living cells. The 
attempt to constitute the mysterious mitochondria into 
permanent cell-organs is equally opposed ; he asserts 
that they are secondary formations, and that in the 
growing point of Anthoceros the youngest cells are 
devoid of them but that they appear in the older cells. 
The great defect of Lundegardh’s exposition seems 
to us to be his failure to show how a mixtyre of sub- 
stances with their consequent reactions can be an 
explanation of the typical character and persistence of 
living phenomena. When a mixture of substances is 
enclosed in a test-tube definite reactions are set up 
which progress towards a state of eventual equilibrium, 
and an end-state is reached with a mixture of different 
substances and in different proportions from that with 
which we started. In protoplasm, on the contrary, 
the typical nature and proportions of the mixture must 
somehow be maintained even in spite of increase in 
quantity—and these facts cannot be explained by any 
purely physical and chemical analysis. 
Prof. Nageotte’s book is widely different from the 
other two. Although it professedly deals with therelation 
of matter to life,it really consists of the record of a series 
of fascinating experiments on animal grafts. The 
results obtained are new and startling, but they are 
illustrated by what can only be termed an extremely 
bad series of figures. These are prints from photo- 
graphs, hazy and very insufficiently lettered, and we 
can only deplore that such good work should be mis- 
represented by such feeble illustrations. 
We have said that Nageotte begins by condemning 
vitalism. He states that the essential peculiarity of 
living things is not their chemical constitution, but a 
certain order in what he terms the micellar structure, 
the micellz being supra-molecular complexes. Agreed; 
but it is precisely the genesis and maintenance of this 
order which is the inexplicable fact in living things. 
Nageotte even tries to prove that there is a transition 
between dead proteid and living protoplasm, and as the 
principal support of his anti-vitalistic attitude is based 
on this supposed transition we must examine it in some 
detail. He proceeds as follows: Some dog’s blood 
collected in a test-tube is enclosed in a capsule of 
collodion open at one point. This is introduced into 
the peritoneal cavity of another dog, the open end of 
the capsule being in contact with the peritoneum. At 
the end of eight days the capsule is found to be com- 
pletely encysted: the blood has clotted by the forma- 
tion of radiating fibres of fibrin, but the opening of the 
capsule is plugged by a cork of fibrous tissue richly 
supplied by the host’s blood-vessels. Now Nageotte 
maintains that the regularly arranged bundles of fibres 
of the fibrous tissue are produced by the gradual trans- 
NO. 2777, VOL. 111] 
NATURE 
[JANUARY 20, 1923 
formation of the radiating fibrin fibres ; that the im- 
migration of fibroblasts (.e. connective tissue cells) is 
secondary, and finally that these elementary fibres can 
grow by intussusception from the fluid surrounding 
them. The whole of the supposed transition is based 
on the arbitrary inclusion of intercellular substance in 
the term living matter. Nageotte protests vehemently 
against what he terms the ‘‘ exoplasmic theory,” 7.e. 
the view that this substance is the product of the 
secretion or bodily alteration of the exoplasm of the 
connective tissue cells; he terms it “the internal 
medium.” But if he were an embryologist instead of 
merely a surgeon and an anatomist, he would see clearly 
that historically there is no other possible origin for 
his internal medium except the secretion of the sur- 
rounding cells: and he himself admits that subsequent 
changes in it only take place under the influence of 
living cells. in the neighbourhood. Whether this 
influence is exercised, as he supposes, by the emission of 
ferments or by the production of secretion is a minor 
matter. If in company with the vast majority of 
histologists we regard the intercellular material as 
dead, then the validity of the supposed transition is 
destroyed. 
Among the most startling of Nageotte’s results is 
the discovery that it is possible to graft into a living 
animal a piece of connective tissue which has been pre- 
served in alcohol or formaline. A piece of tendon thus 
treated introduced under the skin of the ear of a rabbit 
becomes invaded by the surrounding “‘ fibroblasts ” ; 
its bundles of fibres become connected up at their ends 
with the surrounding connective tissue, and thus 
definitely incorporated in the skeletal framework of 
the ear. When a piece of dead cartilage is similarly 
treated still more curious results ensue. The neigh- 
bouring “fibroblasts” surround it and form a new 
perichondrium. ‘These cells invade the capsules of the 
cartilage laid open by the section. These invading 
tongues burrow into the cartilaginous substance, form- 
ing cavities which they surround by newly formed bone, 
although there is normally no bone whatever found in 
the rabbit’s ear. 
If a segment of an artery of one dog preserved in 
alcohol be inserted between the cut ends of the artery 
of another dog, it becomes clothed with an endothelium: 
its layers of elastic and connective tissue become con- 
tinuous with those of the artery of the other dog at 
both ends ; and it becomes provided with new smooth 
muscle fibres, which appear from the transitional 
forms observed to be modifications of connective tissue 
cells. 
We pass now to Nageotte’s experiments with cut and 
regenerating nerves and nerve grafts. As all are aware, 

