Il -
5 8 O B S E R \ ^ A T I O N S ON THE
Whilft I mention the above as the primary purpofes which the ftruiture
of the ganglia points out, I think it highly probable there may be other
yet latent purpofes ferved by them.
T . VIII.
A s the heart and bowels of the abdomen are remarkable for the various
fources of their nerves, and for the number of ganglia through which thefe
are tranfmitted, and alfo for their extenfive fympathy with other organs,
we feem to receive a confirmation of what I alledged above in CHAP. XVII.
that the extent of the fympathy of our organs is in proportion to the number
of connedions their nerves have with different parts of the brain.
C H A P^
2. De faire parveair les nerfs commodement par des dire£lions différentes aux parties :
• 3. De réunir plufieurs petites fibres nerveufes en un gros nerf : Might have been nearly as well exccuted
without ganglia as with chem ; and that they are magazines for furnilhing cellular membranes
and coats to the nerves, as he contends, feems a frivolous hypothefis, not conneÛed.with any appearance
in their texture.
That ganglia do not ferve to render motions independent of our will, as an ingenious autlior has
fuppofed, is evident, without obferving more than that all the branches of the fifth pair, and the po*
Aerior half of all the fpinal nerves of the voluntary mufcles, pafs through ganglia.
N E R V O U S S Y S T E M . 59
C H A P T E R XX.
Of Spheroidal Bodies which, in fome Animals, make Part of
the Nervous Syftem.
T N fiflies of the genus gadus of Linnaeus, to wit, in the cod, the whiting,
and the haddock, I have difcovered a great niimber of fpheroidal
bodies, between the dura and pia mater, on the outfide of the brain, cerebellum,
and top of the fpinal marrow, lodged in a vifcid clear humour,
which is interpofed between the cranium and brain *. Other fuch bodies
are fo\md between the membranes of the femicircular canals of their ear,
and the canals of bone which contain them, difperfed in a vifcid humour
which is interpofed between thefe ofleous and membranous canals^
When we carefully obferve the fituation of thefe fpheroidal bodies, they
feem to be fupported, in their places, not merely by the vifcidity of that
humour, but to have blood-veiTels, and likewife white fibres, partly cellular,
and perhaps, in the ear^ partly nervous, connected to them.
A pair of very large nerves, which feems analogous to our fifth pair f ,
and all the nerves from the fpinal marrow, are covered with thefe fpheroidal
bodies as with a coat of mail, from their origin to their divifion into
branches when the fpheroidal bodies become fewer in number, fo that
the nervous cords are feen in their interftices. The minute branches or
terrmnations of the nerves are not attended by thefe bodies, but are quite
funilar to the nerves in other fiilies or in other claffes of animals ||.
Thefe
• See Tab. XXXII. Fig. i. D. E. F.
t See Tab. XXXII. Fig. 1. M. M.
i See'Tab. XXXII. Fig. I. and 2. Tab. XXXm. Fig. i. Tab. XXXIV.
li See Tab. XXXIU. Fig. i. B. C. Tab. XXXIV. Fig. i.