From article:

Caption: 'Transverse section of tail of large Skate (Raia batis) (actual size). sp. c. spinal canal; v. vascular canal containing caudal artery and vein; m. muscles; o. electrical organ.' (141)

'The relations of the electrical organ to surrounding parts can be best understood from the engraving (Fig. 1), which represents in outline a transverse section of the tail, where it occupies most space. It is seen that its surface is mapped out into polygonal areas by the cut edges of the longitudinal septa, and that these radiate more or less distinctly from the obtuse angle on the median side of the section, which corresponds to the line of attachment along which the vessels and nerves enter. It is also noticeable that the external areas are arranged concentrically round the central ones.' (141)