Contributions from the E.M. Museum of Geology and Archaeology of Princeton College. Bulletin no. 3.

  • College of New Jersey (Princeton, N.J.). E.M. Museum of Geology and Archaeology.
Date:
1883
Catalogue details

Licence: Public Domain Mark

Credit: Contributions from the E.M. Museum of Geology and Archaeology of Princeton College. Bulletin no. 3. 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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    floccuH and trigeminus nerves are quite pig-like. The casts have been reduced to three ill-defined classes, represented by Figs, i, 2, 3, 4. Fig. 4 represents a class differing somewhat from that represented by Fig. i. The general similarity of the main fea- tures of the casts has already been pointed out. It remains only to notice some of the distinctive characters of each class. Fig. I represents a class having its hemispheres marked by very prom- inent gyri. The median gyrus unites with the medilateral pos- teriorly. The anterior extremity of the temporal lobe is well marked. In Fig. 4 the transverse axis of the hemispheres, is relatively longer than in Fig i, consequently the cerebrum pre- sents a more oval appearance dorsally. A cast considerably larger than Fig. i, but resembling it in outline, probably repre- sents a larger animal of the same species. Fig. 2 represents a class having the longitudinal axis relatively larger than the classes represented by Figs, i and 4. The extension of the axis is mainly due to the forward growth of parts anterior to the temporal lobe. The median gyrus becomes continuous with the orbital. The median and medilateral gyri do not become com- pletely continuous, being separated by a shallow fissure. Fig. 2 a represents a cast probably belonging to this class, which has had its prominent features somewhat obscured by a superficial de- posit of matrix. The former is from Chalk Bluffs, Colorado, the latter from the Bad Lands, Dakota. Fig. 3 represents a well- defined class, where the longest longitudinal axis of the hemis- pheres was apparently somewhat shorter than the longest trans- verse axis. Its chief peculiarity consists in the marked diverg- ence of the median and medilateral gyri from the. meson posteriorly. This cast is moulded from the light-colored matrix found at Chalk Bluffs, Colorado. The darker-colored matrix, noticeable in other casts, is common in the Dakota Bad Lands. The casts probably represent several species of Oreodon, includ- ing O. Ciilbertsonii, O. Major and O, Gracilis. In the appended measurements, the cerebrum is m'easured dorsally, hence its longitudinal axis is not extended through the restored olfac- tory lobes. Measurements. Cast I. (Fig. I.) Longest longitudinal axis of cerebrum transverse “ “ “ “ vertical “ longitudinal “ “ cerebellum “ transverse “ vertical mm. • ••47 ...4a ...31 ...as ...ay ...33 Cast II. (Fig. a.) mm. Longest longitudinal axis of cerebrum 45 ^ transverse “ “ “ 39 . •• vertical “ “ “ .••-34 “ longitudinal “ “ cerebellum 34 “ transverse “ “ “ ••••3° The vertical axis of cerebellum in all cases is measured through the entire epenccphalon. Cast III. (Fig. 3.) Longest longitudinal axis of [cerebrum mm. •* transverse •* vertical i t 41 23-4 “ longitudinal ii cerebellum “ transverse “ vertical (1 If