1885. ] Fhysiology. 619 
however, is admirable and the historical introductions might have . 
been made of much value had the same attention been paid to the 
literature of other nations as has been given to that of the French. 
e authors study separately: 1. The innervation of the cutane- 
ous blood-vessels. 2. The dilator-function of the grand-sympa- 
thetic. 3. The vaso-dilator nerves of the external ear. 4. The 
vaso-dilator nerves of the inferior limbs. 5. Influence of the blood 
of asphyxia on the nervous mechanism of the circulation. The 
authors are convinced that the slow rhythmic contractions which 
small arteries, as those of the rabbit’s ear can be seen to undergo 
are not peristaltic, proceeding from the heart outwards, but in- 
volve the whole vessel simultaneously. In nearly all nerve trunks 
containing vaso-motor fibers, as the sciatic, the cutaneous and the 
sympathetic nerves, the vaso-motor filaments are of two kinds, 
vaso-dilator and vaso-constrictor. Efferent or centrifugal vaso- 
motor impuises, like ordinary motor discharges, all leave the 
spinal cord by way of the anterior spinal nerve roots; on the 
other hand all afferent or centripetal vaso-motor impulses enter 
the spinal cord through the posterior spinal nerve roots. The 
chemical condition of the blood determines largely the vaso- 
motor coordination between the vessels of the skin and of the 
viscera; asphyxia produces a dilatation of the vessels of the skin 
and a simultaneous contraction of those of the viscera. The 
direct action of dilator nerves traveling in the sympathetic can be 
demonstrated on the dog; stimulation of the sympathetic nerve in 
the neck causes flushing of the mouth and face on that side, 
The most valuable part of the work is that which considers the 
vaso-motor functions of the sympathetic ganglia. se 
tions indicate that these ganglia are automatic vaso-motor centers 
from which impulses go out to the muscular coats of the vessels 
and keep them in a state of tonic contraction. Dilation or, on 
the contrary, stronger contraction of the vessels is brought about 
indirectly by either stimulation or inhibition of the activity of the 
appropriate sympathetic ganglia through impulses reaching these 
ganglia from the spinal cord along either vaso-constrictor or vaso- 
dilator spinal nerves. The physiological classification of nerves 
announced by Borden and by Bichat is still supported by fact; 
namely, that the cerebro-spinal system presides over the functions 
of animal life and of relation; while the sympathetic system is 
concerned with the nutrition and vegetative life of the body. 
THE PHYSIOLOGICAL PURPOSE OF TURNING THE INCUBATING 
Hen’s Ecc.—The setting fowl frequently turns her eggs during 
incubation and when this process is carried on artifically, mechani- 
cal means must be adopted to effect the same purpose, M. Dareste 
finds that during the first week of artificial incubation eggs which 
are turned develop in essentially the same manner as those which 
are allowed to rest, but the monstrosities which have already been 
