The human brain : its configuration, structure, development, and physiology : illustrated by references to the nervous system in the lower order of animals / by Samuel Solly.

Date:
1836
Catalogue details

Licence: Public Domain Mark

Credit: The human brain : its configuration, structure, development, and physiology : illustrated by references to the nervous system in the lower order of animals / by Samuel Solly. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    57/542 (page 35)
    by which the animal is informed of the existence of surrounding things, and is fitted to act upon these to the extent of its limited necessities. The next specimen of a nervous system to which we shall direct our attention is taken from the second subkingdom; the Diplo-neurose or Articulated animals of Cuvier. This is almost as simple in its arrangement as that just referred to, although in general appearance it approaches more nearly to that of the higher orders. Plate I. fig. 5., taken from Dr. Grant’s Out- lines of Comparative Anatomy, represents the nervous system of the common Sandhopper, or Talitrus Locusta; and it will be seen that here likewise all the ganglia are of equal size and nearly at equal distances: this form of nervous system is seen in the embryos of the higher or- ders of the Crustacea. The next step onwards in the evolution of the nervous system consists in the approach and close connexion of the two longitudinal cords and their accompanying ganglia, or to concentration of these into a single cord as well as single ganglia. This form is beautifully illustrated by that of the Cy- mothea, Plate I. fig. 6. In the Lobster we meet with the same arrange- ment of neurine into single ganglia as we observe in the Cymothea; but in addition to this, we per- ceive that those which are placed nearest to the head of the animal are much increased in size, a