ELECTRICAL FISHES 



387 



muscle-fibres correspond with the similar cross-bands in the 

 lamellar stratum of the fully - developed plate. Not merely 

 preparations at different stages, but the same individual fibre 

 will present every transition from the " typical striated muscle 

 substance, to the typical meandering stratum of the perfect 

 electrical organ." Still plainer is the homology between the 

 thin, strongly -refractile lamellae of the electrical organ and the 

 arimetabolous (isotropous) layers, and that of the thick, weakly- 



FIG. 253. Raja circvlaris. Portion of L.S. through an electrical goblet. w = nervous and 

 nucleated layer ; m=meandering layer ; a=alveolar stratum. (Ewart.) 



refractile lamellae, with the metabolous (anisotropous) layers of 

 striated muscle, under a very high power. In this process of 

 transformation, the superficial growth of the lamellae increases 

 vertically to the fibre-axis on the one hand in a marked degree, 

 while on the other the height of the layers also increases doubly 

 and trebly. Along with this there are fundamental alterations in 

 the morphological and physico-chemical reaction of the two layers, 

 expressed above all in polarised light by the marked diminution 

 in double refractability, which " in the metabolous layers becomes 



