PLATE 1" 



EXPLANATION OF FIGURES 



1 Photomicrograph of a teased preparation of the nervus ischiadicus of a 

 normal fowl. Marchi method. Zeiss 4 X 16 mm. 



2 Photomicrograph of a teased preparation of the nervus ischiadicus of 

 fowl No. 2, after 24 days on an exclusive diet of polished rice. Every fiber shows 

 degeneration. Advanced degeneration is seen in 4 fibers. Marchi method. 

 Ziess 4 X 16 mm. 



3 Fiber from the nervus ischiadicus of fowl No. 6 — 3 days in paralysis — 

 showing marked degenerative changes, a swelling of the fiber at a, b, etc., and 

 no nuclei of the neurilemma sheath, m is a hollow globule of degenerated myelin 

 containing a segment of the axis cylinder. Marchi method. X 200. 



4 Fiber from the nervus ischiadicus of fowl No. 1 — showing complete altera- 

 tion of the medullary sheath into globules of degenerated myelin. The laminated 

 appearance of the larger globules is seen at m. n and n' are nuclei of the neu- 

 rilemma sheath. Marchi method. X 312. 



* Camera lucida outlines were used in the preparation of all the drawings. 

 The photomicrographs are by Martin and Cortes. 



96 



