M. W. WOERDEMAN: “An Inquiry into the Distribution of Potassium- 
compounds in the electric organ of the Thorn-back (Raja Clavata)”’. 
Electric platelet. 
= bloodvessels. 
medullated nerve. 
Fig. 2. Microphoto of two electric platelets of Raja punctata. (Section of 
frozen organ, treated with potassium-reagent) Exhibits a very black precipitate 
in the electric platelets and little or no precipitate in the jelly-like connective 
tissue between the platelets. 
(Reichert. Objective 4. Ocul. 2). 
remainder of striation. 
Granular layer. 
Juclei encircled 
by granular 
precipitate. 
Nucleus encircled by 
granular precipitate. 
anterior cortical 
layer. 
Inner layer. 
Posterior certical 
layer. 
Fig. 3. Microphoto of an electric platelet of Raja punctata. (frozen section, 
treated with potassium-reagent). 
(Oil-immersion '/ Leitz. Oculair 2). 
Proceedings Royal Acad. Amsterdam. Vol. XXIII. 
