[78] Mivart, The Genesis of Species, 1871, p. 23.
[79] Dohrn, Der Ursprung der Wirbelthiere und das Princip des Functionswechsels, 1875, p 74.
[80] Sigmund Mayer, Die peripherische Nervenzelle und die sympathische Nervensystem, 1876.
[81] On these cells see [note] to § [140].
[82] These terms designate the surface aspect of a transverse section, of what more correctly should be called the gray columna. See [Figs. 3] to [6].
[83] But this only in the higher animals. In reptiles and amphibia the medulla descends into the cervical region, as far as the second and third cervical vertebræ. This should be remembered in experimenting.
[84] Foster and Balfour, Elements of Embryology, Part I., 1874. Comp. Schwalbe, art. Die Retina, in the Handbuch der Augenheilkunde of Graefe and Sämisch, 1874, I. 363.
[85] The development of the olfactory lobe and bulb is similar; it need not be followed here.
[86] German anatomists divide this axis into trunk and crown (Hirnstamm and Hirnmantel). There is convenience in this division. If we remove all the gray matter of the cerebrum, with all the white matter radiating from it, until we again come upon gray matter—and if we then cut the cerebellum from its descending strands of white matter—we shall have removed the crown, and leave the trunk remaining. This trunk is constituted by the corpora striata, nucleus lentiformis, optic thalami, corpora quadrigemina, crura cerebri, pons, medulla oblongata, and medulla spinalis. From this trunk all the organs of the body are directly innervated (except those innervated from the sympathetic?).
[87] “On s’est préoccupé du rôle spécial que pouvaient jouer les ganglions périphériques situés dans le voisinage de certaines organes; et on a prétendu que les nerfs ne jouissaient de leur propriété d’agir sur ces organes qu’après avoir traversé ces ganglions. On avait admis que l’excitation portée sur le filet nerveux avant son entré dans le ganglion restait sans effet; que pour obtenir l’action excitatrice des fonctions de l’organe il fallait exciter le nerf entre lui et le ganglion voisin.”—Claude Bernard, Systéme Nerveux, II. 169. But on proceeding to verify these statements by experiment, Bernard is led to the conclusion, “que le ganglion n’a pas d’influence propre sur le mode de l’excitation transmise à l’organe.”