538 HENRY M. BERNARD, 



actually found. There was no appreciable difiference between the length 

 of the fully contracted elements and the anisotropous layer in the 

 expanded elements. From this it follows that the total longitudinal 

 contraction of the "element" could be explained by the absorption of 

 the isotropous substance, and by this alone. 



I further analysed Engelmann's elaborate series of measurements ^ ). 

 The Roman numbers in the first column refer to Engelmann's cases, 

 selected because they specify the stages of contraction measured. In 

 each case, I have marked the figures to be compared with asterisks. 

 I have kept to Engelmann's divisions of the contracting elements into 

 separate layers, although, as stated above, I do not believe in the per- 

 sistence of the isotropous layers as separate layers, either in the tran- 

 sition or contracted stage. 



Engelmann's comparative lengths of the anisotropous 



and isotropous layers at different stages of contraction 



of the muscle element. 



I 



•{ 



{ 

 { 



III 



IV 



VIII. 



X. 

 XI. 



1) Mikrometrische Untersuchungen an contrahirten Muskelfasern, in; 

 Pflüger's Archiv, Bd. 23, 1880. 



