THE EFFECT OF FATIGUE ON THE NUCLEI OF VOLUNTARY 
MUSCLE CELLS. 
BY 
P. K. GILMAN. 
From the Anatomical Laboratory of the Johns Hopkins University, Baltimore, Md. 
With 4 Text FIGURES. 
While a great deal of work has been done concerning the effect of 
fatigue on the cells of the nervous system, I can find nothing in the 
literature on similar changes in the nuclei of muscle cells. In an article 
by Scheffer” the subject of the histological effect of muscle fatigue is 
taken up from a different standpoint. 
Below are given the results of a number of experiments upon embry- 
onic and adult muscular tissue. The muscle in the tail of the tadpole 
was used for the first series of experiments and the gastrocnemius of the 
frog for the second. The work was undertaken at the suggestion of Dr. 
C. R. Bardeen. 
A. Tait Muscues or Tappo“e.—Various methods for fatiguing the 
swimming muscles of the tadpole were used, that of keeping the animal 
constantly irritated by means of a long haired brush revolving within 
the dish, proving the best. A shaft was suspended perpendicularly in 
the center of the dish its upper end bearing a wheel connected by a belt 
to a water wheel. At the lower end of the shaft an arm was attached 
which extended out from the center to the edge of the glass dish a short 
distance above the surface of the water. To this arm the brush was 
attached along its lower border, the hairs of the brush extending to the 
bottom of the dish and stirring up thoroughly the water and animals 
when the apparatus was set in motion and the arm revolved about the 
central shaft. After the animals became too fatigued to swim against 
the current produced by the apparatus, the hairs rubbing over them 
would stimulate the tadpoles to further movements. A stage was finally 
reached when no further movements could be obtained even upon violent 
stimulation such as pinching with forceps or pricking with a needle. In 
‘Scheffer, W., Ueber eine mikroskopische Erscheinung am ermiideten Muskel. 
Miinchner Med. Woch., 17 Juni, 1902. 
