. On the anatomy of vertebrates [electronic resource] . t-pyramidal and restiformwalls swell outwards, and form lateral 4vagal lobes, large andnodulated in the Carp, fig. 178, h, which is so tenacious of life. Thevagal lobes are enormously developed in the Torpedo; they join thetrigeminal lobes, and present a yellowish colour in the recent fish :many non-nucleated cells are present in their substance ; they giveorigin to the nerves of the electric organs, and have been called4 lobi electrici; but the vagal lobes are scarcely less remarkablefor their size in the Gymnotus, where they have no dir
. On the anatomy of vertebrates [electronic resource] . t-pyramidal and restiformwalls swell outwards, and form lateral 4vagal lobes, large andnodulated in the Carp, fig. 178, h, which is so tenacious of life. Thevagal lobes are enormously developed in the Torpedo; they join thetrigeminal lobes, and present a yellowish colour in the recent fish :many non-nucleated cells are present in their substance ; they giveorigin to the nerves of the electric organs, and have been called4 lobi electrici; but the vagal lobes are scarcely less remarkablefor their size in the Gymnotus, where they have no direct con-nection with any of the nerves of the electric organs. In theCod the vagal ganglions are obsolete, and the nodulus slightlyswells above, and obliterates the 4 calamus scriptorius. In theLucioperca the vagal lobes are not very distinct, but they mark 1 Homologous with the filamenti arcifovmi of Rolando, lviii. p ] 70, t. i. fig. 2. 2 These are called vordere pyramiden by Dr. Stannius. lvi. p, 43. 3 xx. vol., nr. p. 22; Prep. no. I. T. 274 ANATOMY OF VERTEBRATES. the commencement, and form the broadest part, of the very longmednlla oblongata, the restiform tracts diminishing in size as theyadvance. In no other Vertebrates save Fishes are the vagal lobesand the nodulus present. The posterior pyramids, which are the anterior continuation ofthe posterior myelonal columns, diverging as they are pushedaside by the deeper-seated tracts that form the floor of the fourthventricle, and combining with the lateral columns to form thecorpus restiforme and the basis of the vagal lobes, again quitthose columns, converge, ascend, and unite together above theanterior opening of the fourth ventricle: they there form eithera simple bridge or commissure, fig. 173, c, or are developedupwards and backwards into a ganglionic mass, overarching theventricle ; this mass is the cerebellum, figs. 174—179, c. It is173 formed chiefly by the post-pyramidal columns, but doubtless derives s
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