aay ee 
teased fragments of the ganglion. Occasional unipolar cells were regarded 
as multilated elements from which one of the processes had been torn 
away by the needles. 
The application of more modern staining methods now makes it clear 
that these interpretations were erroneous. These cells are from the oculomotor 
region of the ganglion, and one of the supposed processes is a foreign fiber 
ending on the cell-body in the form of a firmly affixed calyx, which often 
successfully resists the teasing needle. As is shown in Figure 14, a somewhat 
macerated cell stained in acid fuchsin and isolated by teasing gives 
little evidence of the exact relation between it and the two fibers with 
which it is connected. The study of methylene blue and silver prepar- 
ations has taught us, however, to recognize in the fiber showing the 
heaviest axis cylinder an oculomotor neurite, while the more slender 
medullated axone is unquestionably the process arising from the cell, 1. e., 
a ciliary neurite. 
Physiological Significance of Calyx Endings. By means 
of their expanded calyx endings the oculomotor neurites are brought 
into close contact with comparatively large surface areas of the ganglion 
cells. The break in the continuity of the two neurones is much less 
than that found in a typical sympathetic ganglion, where pericellular 
plexuses of fine fibrils convey the nervous impulse from the pregang- 
lionic fiber to the postganglionic or sympathetic neurone. Reasoning 
from the anatomical conditions one might predict greater difficulty 
in interrupting the neryous impulse in the ciliary ganglia of birds 
than in ganglia typically sympathetic in their synaptic relations. That 
this has been the experience of experimenters, the following citations 
will show. 
It is well known, from the researches of Langley, that a small 
quantity of nicotin will prevent the passage of nervous impulses through 
sympathetic ganglia, while spinal ganglia, in which the path is not 
broken by synapses, remain unaffected This inhibition in sympathetic 
ganglia is believed to be due to the paralyzing effect of the drug on 
the pericellular baskets around the sympathetic cells. The ciliary ganglion 
of mammals, in which the oculomotor fibers end in pericellular networks 
(Michel, ‘94; Sala, :10; v. Lenhossék, :10) responds readily to 
nicotin, behaving in this respect like a sympathetic ganglion (Langley 
and Anderson, ’92, Marina, ’99). The ciliary ganglion of birds, on 
the contrary, resists the action of nicotin nearly as successfully as a 
spinal ganglion. Consiglio ( :00), as reported by Langendorff 
( :00), subjected the ciliary ganglion of birds to nicotin, but found 
that stimulation of the third nerve was still followed by constriction of 
the pupil, i. e., the nervous impulses were not interrupted in the 
