FOOTNOTES:
[a] Thus Swine, for Instance, who dig in the Earth for Roots and other Food, have their Neck, and all Parts of their Head very well adapted to that Service. Their Neck short, brawny, and strong; their Eyes set pretty high out of the Way; their Snout long; their Nose callous and strong; and their Sense of Smelling very accurate, to hunt out and distinguish their Food in Mud, under Ground, and other the like Places where it lies concealed.
[] What hath been said of Swine is no less, rather more remarkable in the Mole, whose Neck, Nose, Eyes and Ears, are all fitted in the nicest Manner to its subterraneous Way of Life.
[c] Willis Cereb. Anat. cap. 6. Cumque huic Deus os sublime dederit, &c.
[d] Id. paulo post. In capite humano Cerebri & Cerebelli, &c.
[e] See [Book IV. Ch. 2. Note (kk).]
[f] Arteria Carotis Aliquanto posterius in homine quàm in alio quovis animali, Calvariam ingreditur, scil. juxta illud foramen, per quod sinus lateralis in Venam jugularem desiturus cranio elabitur; nam in cæteris hæc arteria sub extremitate, seu processu acuto ossis petrosi, inter cranium emergit: verùm in capite humano, eadem, ambage longiori circumducta (ut sanguinis torrens, priusquam ad cerebri oram appellit, fracto impetu, leniùs & placidiùs fluat) prope specum ab ingressu sinûs lateralis factum, Calvariæ basin attingit;——& in majorem cautelam, tunicâ insuper ascititiâ crassiore investitur. And so he goes on to shew the Conveniency of this Guard the Artery hath, and its Passage to the Brain, and then saith, Si hujusmodi conformationis ratio inquiritur, facilè occurrit, in capite humano, ubi generosi affectus & magni animorum impetus ac ardores excitantur, sanguinis in Cerebri oras appulsum debere esse liberum & expeditum, &c. Atque hoc quidem respectu differt Homo à plerisque Brutis, quibus, Arteria in mille surculos divisa, ne sanguinem pleniore alveo, aut citatiore, quàm par est, cursu, ad cerebrum evehat, Plexus Retiformes constituit, quibus nempe efficitur, ut sanguis tardo admodum, lenique & æquabili fere stillicidio, in cerebrum illabatur. And then he goes on to give a farther Account of this Artery, and the Rete mirabile in divers Creatures. Willis, ibid. cap. 8.
[g] Galen thinks the Rete mirabile is for concocting and elaborating the Animal Spirits, as the Epididymides, [the Convolutions κιρσοειδοῦς ἕλικος] are for elaborating the Seed. De Us. Part. L. 9. c. 4. This Rete is much more conspicuous in Beasts than Man; and as Dr. Willis well judges, serves, 1. To bridle the too rapid Incursion of the Blood into the Brain of those Creatures, whose Heads hang down much. 2. To separate some of the superfluous serous Parts of the Blood, and send them to the Salival Glands, before the Blood enters the Brain of those Animals, whose Blood is naturally of a watery Constitution. 3. To obviate any Obstructions that may happen in the Arteries, by giving a free Passage through other Vessels, when some are stopped.
In Quadrupeds, as the Carotid Arteries are branched into the Rete Mirabile, for the bridling the too rapid Current of Blood into the Brain; so the Vertebral Arteries, are, near their Entrance into the Skull, bent into an acuter Angle than in Man, which is a wise Provision for the same Purpose.
CHAP. III.
Of the Necks of Quadrupeds.
From the Head pass we to the Neck, no principal Part of the Body, but yet a good Instance of the Creator’s Wisdom and Design, inasmuch as in Man it is short, agreeable to the Erection of his Body; but in the Four-footed Tribe it is long, answerable to the Length of the Legs[a], and in some of these long, and less strong, serving to carry the Mouth to the Ground; in others shorter, brawny and strong, serving to dig, and heave up great Burdens[].
But that which deserves especial Remark, is that peculiar Provision made in the Necks of all, or most granivorous Quadrupeds, for the perpetual holding down their Head in gathering their Food, by that strong, tendinous and insensible Aponeurosis, or Ligament[c] braced from the Head to the middle of the Back. By which means the Head, although heavy, may be long held down without any Labour, Pain, or Uneasiness to the Muscles of the Neck, that would otherwise be wearied by being so long put upon the Stretch.