Fig. 30.
THE Brain lying on its Basis after its Two Hemispheres are cut off, and the Blood-Vessels Injected with Wax; the Cerebellum remaining intire.
A A, The Inferior Part of the Fornix as it Appears when cut from its Roots b, b. and turn'd Back, with Part of the Corpus Callosum remaining on it.
a a, The Blood-Vessels that Appear on this Inferior Sur∣face of the Fornix.
b b, The Roots of the Fornix.
c c, The Thalami Nervorum Opticorum or Beginnings of the Optick Nerves.
δ δ, The Corpora Striata; that of the Left Side remaining Whole; the Right being Divided to shew its Striae.
d d, The Crura Fornicis where they begin to Wind down on the Sides of the Crura Medullae Oblongatae: These Crura of the Fornix are call'd Hyppocampi or Bombycini.
e e, The Plexus Choroides whose Arteries Arise from the First Branches of the Cervical Artery e e, Appen. Fig. 28.
f, The Meeting of the Plexus at the Root of the Fornix, where its Two Veins pass to its other Part g g.
g g, The other Part of the Plexus Choroeides, whose Arteries Spring from the Second Branches of the Cervical Artery, join'd with the First by Communicant Branches; which do not Appear here, by reason they lie under the Crura Forni∣cis d d.
h h, Two Veins which Arise from the Upper-parts of the Plexus Choroeides, and pass the Third Ventricle to the other Part of the same Plexus g g, near the Nates and Testes.
i i i i i i, The Branches of the Carotide Arteries cut off, as they Appear Injected with Wax, and passing between the Cortical Foldings of the Brain.
k, A Branch of a Vein which passes according to the Length of the Corpus Striatum of the Left Side, and Dis∣charges its Blood into the Veins of the Plexus Choroeides; that of the Right Side being taken away to shew the Striae.
l, Part of the Rima of the Third Ventricle that do's some∣what Appear under the Vein, h.
m, A long Medullary Tract between the Corpus Striatum and Thalamus Nervi Optici, call'd by Dr. Willis, Processus Me∣dullaris Transversus.
n n n n, The Centrum Ovale of Vieussens.
o, That Part of the Corpus Callosum by Vieussens, call'd For∣nix Vera, between which, and the Fornix p, is plac'd the Sep∣tum Lucidum, Dividing the Fore-part of the Right Ventricle of the Brain from the Left. This Septum by some call'd Spe∣culum, is a Continuation of the Inward Membrane which In∣vests the Two Superior Ventricles, meeting in their Upper∣parts not unlike the Pleura on the Sternum, where it Composes the Mediastinum, and Divides the Cavity of the Thorax. In the Upper-part of this Septum I have more than once seen its Duplicature fill'd with a Watrish Humour in Hydropick Brains, as Vieussens also takes Notice.
O, The Fourth Sinus of the Dura Mater fill'd with Wax.
P, The Longitudinal Sinus cut off, where it meets the Fourth and Two Lateral Sinus's, call'd Torcular Herophili.
Q Q, The Two Lateral Sinus's also Extended with Wax.
R, A Vein fill'd with Wax on the Second Process of the Dura Mater.
r, Some Branches of Veins as they Appear on the Second Process of the Dura Mater.
p, The Fornix cut off near its Two Roots.
q q, Some Lymphe-ducts on the Plexus Choroeides which Ac∣company the Vein h h h, in their Way to the Glandula Pinia∣lis not seen in this Figure; that Gland being plac'd under the Fornix A, a, with the Nates and Testes, as is Exprest Tab. 10. Fig. 1. Q, O, O, P, P.
These Lymphe-ducts perhaps were seen by that Accurate Anatomist. Mons. Beddevold, in Examining an Ox's Brain; of which he Communicated an Account to the Accurate Nuck as Mons. Beddevold himself told me, and Appears in an E∣pistle at the End of Nuck's Adenographia Curiosa. Vidi, says he, Lymphaticum in Cerebro Bivino, quod examine tuo (ut Originem scias & Insertionem) erit Dignissimum. Non longe à Glandula Pi∣neali, à qua Ramos forte habet, incumbit Plexui Choroidaeo ad In∣fundibuli latera sese extendens.
S S S S, The Cerebellum Cover'd with the Second Process of the Dura Mater in its Upper-part, and the Dura Mater it self on the Hinder-part.
f f, Some Branches of Veins which Appear fill'd with Blood on the Dura Mater, Covering the Back-part of the Cerebel∣lum; which vary in their Course from those Subjacent Vessels on the Pia Mater, which are immediately Distributed on the Cerebellum it self, and faintly Appear in those Stroaks running somewhat Parallel with the Lateral Sinus's.
T T, Parts of the Vertebral Arteries.
V V, The Vertebral Sinus's on which the Wax Appears Extravast, as in Fig. 28. F.
W, The Back-part of the Medulla Oblongata Cover'd with the Dura Mater.
x x, A Probe Supporting the large Veins of the Plexus Cho∣roides in the Third Ventricle of the Brain.
† † † The Medullary;
* * * The Cineritious Part of the Brain.