180 JoURNAL OF COMPARATIVE NEUROLOGY. 
of cutaneous sense organs and the terminal nuclei within the 
medulla oblongata to which these organs are related. 
The topography of the chief nerve trunks having already 
been given by Wricut and the chief morphological features of 
their central termini by Kinespury, I shall here confine myself 
to the points of greatest value to the theory of nerve compo- 
nents; viz., the exact courses of the components through the 
V + VII and the IX + X ganglionic complexes and the exact 
peripheral relations of the communis and lateralis components 
of these nerves. The motor nerves will detain us in only a few 
cases and the orbital nerves have been fully described by my 
pupil, Mr. Workman (‘00). Ameirus melas, JORDAN and CopPE, 
is the species most carefully studied and the microscopic exam- 
ination of transverse sections through the whole body of the 
adult fish stained by the WEIGERT process is the method chiefly 
relied upon. Three specimens were sectioned transversely. 
The descriptions and illustrations following are all based on the 
left side of one of these specimens unless express statement to 
the contrary is made. 
The details of the method in the case of this specimen are 
as follows: A small adult was hardened for 27 days, until fully 
decalcified, in FLEmMiING’s stronger fluid. After five months in 
cedar oil it was embedded in paraffin ard cut transversely into 
serial scctions 13 1-3 y thick as far back as the middle of the 
dorsal fin. The sections fixed to the slide with Mayer’s albu- 
men were mordanted in Eruicki’s fluid over night, stained in 
Kuttscuitzky’s acid hematoxylin 24 hours and decolorized in 
a mixture of equal parts of saturated solution of lithium car- 
bonate and 1% solution of ferricyanide of potassium. 
The work will be divided into two parts, (1) the descrip- 
tion of the nerves-and (2) the account of the cutaneous sense 
organs. As our interest in Part I centers largely about the in- 
nervation of the sense organs, it will be necessary in this place 
to anticipate briefly a few points which are treated more at 
length in Part II. The organs now under consideration, as in- 
dicated above, fall into two great groups in correlation with their 
nerve supply, which I have termed the communis and the acus- 
