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ciliary fibers of the communicating ramus as the sensory component 
of the trigeminal innervation of the eyeball. 
Nature of the Ciliary Ganglion of Birds. With the fore- 
going analysis of its structure and connections before us, in what light 
are we to regard the ciliary ganglion of birds? Is it a cerebro-spinal 
ganglion, a sympathetic ganglion, a combination of the two, or a ganglion 
Sul generis? 
The ganglion in birds is plainly not cerebro-spinal, because: (1) it 
does not originate from the neural crest (Carpenter, :06); (2) the 
processes of its cells do not show T-shaped divisions, with one branch 
entering the central nervous system; (3) it lies on the trunk of a motor 
nerve, some of the neurites of which end on its cells; (4) it appears 
to be purely motor in function. 
The ganglion is not sympathetic in the sense that it is the most 
cephalic representative of the gangla of the sympathetic chain, because: 
(1) there is no evidence that its cells are in any way connected with 
the cervical sympathetic; (2) the cells are unipolar, not multipolar, as 
are the sympathetic cells, and they are in large part embraced by calyx 
endings or modifications of these, which are unknown in the sympa- 
thetic system; (3) the ciliary ganglion cells are on the average somewhat 
larger than sympathetic cells, and have better developed capsules with 
amphicyte nuclei; (4) it is probable that the ganglion receives no sen- 
sory fibers comparable with those contributed by the spinal ganglia to 
the sympathetic system. 
It follows as a corollary from these considerations that the cilary 
ganglion of birds cannot be looked upon as a composite cerebro-spinal 
and sympathetic ganglion. 
Are we then to accept v. Lenhossék’s conclusion that it is a 
ganglion sui generis? Although v. Lenhossék overlooked the con- 
nection with the trigeminus, and consequently could not form a complete 
conception of the relations of the ganglion, he nevertheless acquired 
sufficient evidence from its histological structure to show that it is 
neither cerebro-spinal nor sympathetic. His conclusion was based partly 
on the erroneous view that he was dealing with ,ein Ganglion, das mit 
dem Sympathicus und Trigeminus nichts zu tun hat, sondern ganz und 
gar dem Oculomotorius angehort’”; but as we have seen the connection 
with the fifth nerve, which undoubtedly exists, does not essentially 
alter the case. The structure still remains in all probability ,eim rein 
motorisches Ganglion”. 
While agreeing with the general conclusion of v. Lenhossék, 
and holding that the ciliary ganglion of birds does not belong to the 
sympathetic system proper, I see no reason why it should: not be 
