w
fi i •
I O O B S E R V A T I O N S ON THE
nix, to which they have given the name of Anus, where they fuppofed the
lateral ventricles to communicate with each other, and with the tliird ventricle
But it may be obferved,
r. That no author lias delineated the beginning of the pafTages by which
the lateral ventricles can difcharge their contents into the third ventricle.
2. If a few have dcfcribed the place where we fliall in reality find fuch a
communication, there is fome reafon to fuppofe that they had been led to
the mention of that place, by taking it for granted that the anterior hole
of tlie third ventricle ferved fuch a purpofe, rather than from their having
adlually feen the paffage, as they have not painted, and do not defcribe its
appearance before the fornix is raifed -j*.
2. Thofe who defcribed an anterior hole under the name of Vulva, have
dcfcribed alfo a poftcrior, under the name of Anus; which they fuppofed
to communicate with the anterior ventricles J. Yet it will appear, that this
place (which is bounded behind by the pineal gland and its conneilion to
the commiflura ccrebri poilerior, at the fides, by the peduncles, or medullary
procefl'es, from the pineal gland to the thalami nervorum opticoium,
and before, by the conjoined thalami nervorum opticoi'um) is completely
ihut by a vafcular membrane between it and the fornix.
3. The moil eminent of the late authors who knew the defcriptions of
forjncr authors, and had particularly examined the fubjedl, have doubted
of, or denied fuch communications of the lateral ventricles with each other,
- W i n f l o w , Ahat. Tab. de la Tefte,* VieuITens, Ne u r . Lib. 1. p. 64. - 70. 81. 84 Li eut aud,
Anar. H. 5. S. p. 338.
j- Vieuflcns, 1. c. Lieutaud, Au. U. PI. Set 2. et An. Pr. p. 620.
Î VieuITens, Lib. i. p. 64. Anus vero altcrum ell: foramen fubtus pofticam fornicis partem latitans,
et juxt a nates excavatum, quo intcrmedio anteriores ventriculi cum tertio pariter communicant.
N E R V O U S S Y S T E M .
or with the other ventricles *, or have fo entirely overlooked or mified fuch
communications, that, in the figures they have given, they have not ventured
to paint any of the places at which it had been faid they were to be
found f ; and, as a proof that there is no natural communication, they
have remarked, that, in the hydrocephalus internus, the water had filled
only one of the lateral ventricles J.
C H A P .
* Steno, Cer. Anat. p. 34. ' Ut valde furpeftum habeam utruni ea via (fiflura quae fub fornice latet)
' communicant inter fe anteriores ventriculi et poíteriores,' &c.—Senac, Sup. a l'Hill, du Coeur, Ch.
IO. p. 689. Je vous ai prie d'examiner s'il y a un veritable communication entre les ventricules du
Cerveau : J'ai cru appercevoir une membrane qui couvre des ouvertures qu'on croit libres ^Haller,
El. Phyf. L. 10. § 18. p. 42. ' Leniter tamen impulfo flatu non reperi aërem a destra cavea in fini-
* ílram tranfiifle, aut aquam, in alterius lateris ventriculum miitam, agitafle; § 29. p. 57. Sed ñeque
* anterius, inter fornicis crura anteriora, feptum lucidum et hune plexum, oftium ullum me memini
' inveniffe; neque clan ante me viri viderunt.'—§ 27. p. 55. ' Cum ventriculis anterionbus, quando
' omnia integra funt, non communicat (fcilicet veritriculus tertius) cum illi aqua pieni, ipfe inanis re-
« pertus fît, et cum plexu, quem dLximus, impofito finiatur.'—§ 2g. p. 57. Verum haec imperfet a in
cilia (fcilicet veterum meatus et Willifii vulvam et anum) non a lateralibus ventriculis ad tcrtium, fed
a tertii fuperiori cavea ducunt ad inferiorem.
"t" P . Tarin Adverfaria Anatomica prima, de omnibus Cerebri, See. Defcriptionibus et Iconifmis,
1750. Tab. 2. Fig. I. And the otherwife very accurate ^ d ingenious S. T . Soemmerring de Bail
Encephali, &c. cum tabulis ^ e i s , 1778, Tab. 3. bave delineated the brain cut perpendicularly at its
middle, without pointing out, or feeming to know, the communication of the lateral ventricles with
each other, or with the third ventricle.
In like manner, J.J. Plenck, in his Primae Lincae Ana tomes, 1775, and F. Leber, in his Praelec*
tiones Anatomicae, editio nova, 1778, make no mention of any fuch communications.
1 Kaller, El. Phyf. L. 10. § 18. p. 42.