Contril)iitions from the Biological Laboratory of the U. S. Fish Commission, 
Woods Hole, Massachusetts. 
Tlllt PERIPHERAL NER\ ()US SYSTEM OE THE BONY EISIIES. 
By C. JUDSON HERRICK, 
Professor of Zoology in Denison University, 
Associate in Comparative Neurology, Pathological Institute of New York State Hospitals. 
For sotiie two years past the writer has been engaged upon a niicr()Sco]iical 
examination of the cranial and first spinal nerves of the teleostean fishes. To any- 
one acqnainted with the literature of the nervons system o*^ the fishes it is apparent 
that great confusion prevails regarding the morphology of their peripheral nerves. 
Not only are the homologies with the higher and lower forms obsenre, but even within 
the groups of lishes the variations in the courses of these nerves are so great as to 
complicate the problem enormously. Previous workers along these lines have, as a 
rule, either conllned themselves to gross dissections, or, if the microscopical method 
has been used, such studies have usually been confined to the proximal or root iiortions 
of the nerves. 
Now, by gross methods the topographical relations of the nerves can be and have 
been determined for most of the gr.uips of larger lishes with precision. Indeed, the 
great monograph of Stannius in 1849 has covered this ground with remarkable 
comi)leteness and accuracy. This method, however, leaves ns almost entirely in the 
dark as to the composition of the seveial rami; for it is impossible to determine more 
than apiiroximately what classes of sensory and motor libers are included within each 
nerve, and even such an approximation is often out of the question. On the other 
hand, the microscopical study of the nerve roots and their nuclei 'within the lirain is 
also unsatistactory; for unless we know the exact peripheral distribution of each of 
these roots Ave may be led into grave errors of interjiretation, as several of the most 
recently published researches in tins field forcibly illustrate. 
In view of these facts, the present demand, it seems to me, is for a minute and 
exhaustive study of the exact relations of the several nerve components through the 
entire courses of the several craidal nerves in a few typical lishes. The common 
silverside, Meitidia, so abundant about Woods Hole and other points along the Atlantic 
coast, was chosen as the first type to be examined. These little lishes stand about 
midway between the physostomous and the physoclystous types of fishes, and may be 
regarded as relatively sim])le, generalized forms. Though the organs of special sense 
(eye and ear) are very highly developed, and in some other minor features there is 
considerable specialization, yet the nervous system, as a whole, is very simply and 
evenly developed, and conforms to the central position given to these lishes by the 
taxonomists. 
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