692 ANNA LOWREY 
form several masses of tissue on the sides of the rear of the body. 
The electroplaxes have a myotome arrangement, with the electric 
surface facing posteriorly and with the nutritive surface facing 
anteriorly. In front and behind each electroplax is a layer ot 
connective tissue. The electric surface is evaginated into large, 
short papillae while the nutritive surface is drawn into short, thick 
closely-set papillae. Each papilla system is said to be as thick as 
the middle layer. As in Raja ocellata each electroplax consists of 
three layers, but in this fish the electric and nutritive layers alone 
carry the nuclei, and the middle layer forms a non-striated core. 
The nuclei are near the edge and nearly always in the papillae. 
The nerve fibers approach the electroplax in the posterior jelly- 
like connective tissue as medullated fibers which branch and send 
non-medullated fibers to the ends of the electric papillae. 
From the description of the two types of electric tissue, the un- 
specialized and specialized, electric tissue may be said to possess 
the following characteristics. It is made up of a series of disc-like 
electroplaxes or plates, each of which is composed of three distinct 
layers, the outer ones continuous around the edge and containing 
regularly arranged nuclei. One or both of the outer layers of an 
electroplax may be evaginated into papillae. The electric 
surface always receives the nerve endings. The middle layer is 
the core to each electroplax and may have the striations omitted. 
Each electroplax is a syncytium, well supplied with small blood 
vessels and nerves; is preceded and followed by a space filled with 
jelly-like connective tissue; and is separated from the others by a 
delicate cell membrane, the electrolemma. The whole series of 
plates is surrounded by connective tissue. 
In comparing the structure of the submental filaments of 
Steatogenys elegans with known electric tissue, the following 
similarities are found: The entire series of disc-like plates de- 
scribed in the filaments of Steatogenys elegans, is surrounded by 
a general sheath of connective tissue. Each plate of the series con- 
sists of three layers, two of which are distinctly nucleated, and 
one of which receives the nerve endings; each is preceded and 
followed by a space filled with connective tissue, and is separated 
