Do the cerebellum and the oblongata represent two encephalic segments or only one? : abstract / by Burt G. Wilder.

  • Wilder, Burt G. (Burt Green), 1841-1925.
Date:
[1885]
Catalogue details

Licence: Public Domain Mark

Credit: Do the cerebellum and the oblongata represent two encephalic segments or only one? : abstract / by Burt G. Wilder. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    mesenccphal (optic lobes, etc.) : Harrison Allen, Gegenbaur, Huxley, Kolliker, Lankestcr, Meynert, Mihalkovics, the editors of Quain's Anatomy (eighth and ninth editions), Reichert, Schwalbe, Wiedersheim and the present writer. Omitting lesser parts, the cephalad of these two segments is held to include the cerebellum, together with the portion of the brain stem, immediately connected therewith, and the latter, the part commonly called medulla oblongata. By Von Baer and most other German writers the former is termed hinterhirn, and the latter nachhim. I have adopted the Latin terms employed in Quain's anatomy, viz., epencephal and metencephal, abbreviated to epen. and meten. So far as I know, the only original investi- gators of the subject who have admitted but a single segment caudad of the mesen., are Balfour, Milnes Marshall, Owen and Spitzka, and the last named alone has discussed the question at an}7 length. That the entire region caudad of the mesen. should be regarded as a single segment, of which the cerebellum is merely a dorsal hy- pertrophy has been urged by Spitzka in 1878 ( Jour, of Nerv. and Mental Disease) in 1881, ( Science, April 9), and in a re- cent communication to The New York Medical Record, July 2G, 1884. Before discussing the main question, I desire to correct a mis- apprehension into which Spitzka seems to have fallen respecting nvy own opinions. He implies, first, that I am committed to the view commonly entertained, and, second, that I regard the pons as determining the cephalocaudal extent of the epencephal. On the contrary, as stated in The Medical Record, Aug. 9, 1884, I have repeatedly expressed my sense of the difficult}' of de- termining the precise number and limits of the encephalic segments, and admitted the force of Spitzka's own view. As to the pons, when present it strengthens the floor of the segment, and serves as a landmark of that region ; but it by no means follows, and has never been implied by me, that either of its margins, especially in man, indicates the limits of the epencephalic segment, although in the cat and other mammalia with moderately developed cerebellums, one or both of its margins may closely correspond therewith. In his able presentation of objections to the bisegmental con-