1883. ]. Organic Physics. 145 
tinuous with the muscle sheath. Thus the naked axis cylinder 
of the nerve comes into direct contact with the muscle substance, 
and divides until every muscle fiber has its distinct nerve. The 
nerve extremities spread out on the surface of the fiber into a 
peculiar plate-like mass. But Professor Gerlach asserts that this 
is not the true extremity pf the nerve, but that it sends minute 
fibrils onward, which penetrate the muscle fiber, so that there is 
a most intimate union of nerve and muscle. In the unstriped 
muscles the nerves form delicate plexuses, and subdivide until a 
highly delicate intra-muscular network is produced. Franken- 
hauser traced minute fibrils from this network into the substance 
of the fiber, ending, as he believed, in the nucleolus of the cell. 
But Arnold asserts that a filament is continued through the cell, 
and rejoins the network without. Thus the nuclear fibril seems 
to be the nodal point of a fine intra-muscular network of 
nerves. 
What should we deduce from these facts? The sarcolemma 
of the muscle fibers—by whose aid their separate motions are 
. combined and communicated to the limbs or otherwise distrib- 
uted—is but a continuation of the elastic sheath of the nerves. 
The nerves divide into minute fibrils in the muscles, and each 
muscle fiber appears to be but a mass of contractile matter aggre- 
gated around a delicate nerve extremity. The richly protoplas- 
mic nerve plate may be an arrangement for a final invigoration of 
the nerve current, before entering the fiber. It is not found on 
the slow-moving unstriped muscles, and its purpose may be to 
aid the vigor and rapidity of movement of the voluntary muscles. 
From this point of view a muscle is simply a special aggregation 
of nerve extremities, each of which is surrounded by matter sus- 
ceptible of rapid oxidation, while their sheaths are so combined 
and arranged as to be capable of exerting a powerful strain on 
the limbs or other organs. We may with some reason conclude, 
therefore, that the method of action in all protoplasm is but one; 
While the results are as many as there are diverse arrangements 
Of cells... 
aH There is a third constituent of the sensory and motor organ- 
ism which it is important to here consider—the nerve cell or, 
mass of cells; the ganglion. Under the hypothesis here ad- 
vanced it might, at first thought, be looked upon as an aid in the 
Process of nerve conduction; as a mass of protoplasm intended 
