Carnegie Institution of Washington Publication, Issue 145

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Carnegie Institution of Washington, 1911 - Science
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Page 30 - Length of the maxillary bone . 0.065 Space occupied by ten maxillary teeth 015 Height of crown of second maxillary tooth 014 Height of crown of third maxillary tooth 009 Anteroposterior diameter 003 Transverse diameter 008 Anteroposterior diameter of the eighth tooth 005 Transverse diameter 015 "The present species was about 5 or 6 feet in length, and herbivorous in habit. It was apparently slow in movement, and probably more or less aquatic.
Page 72 - The Brain. When the superior border of the medulla oblongata at the foramen magnum is placed horizontally, the axis of the brain ascends at an angle of 45 towards the frontoparietal fontanelle. The superior surface, anterior to the foramen magnum, is subquadrate in outline, the angles being truncated, and directed anteriorly, posteriorly and laterally. A posterior constriction connects it with the medulla ; and an anterior one defines the middle brain and hemispheres. Each lateral truncated angle...
Page 72 - Varamidse differ from those of other Lacertilia. That is, it is continued between the orbits, so as to enclose the olfactory lobes of the brain within osseous walls. These walls are thin ; especially at the interorbital region, and in the specimen the anterior extremity is so far imperfect as to leave the form of the anterior fundus in doubt. The brain in reptiles, as is well known, does not fill tightly...
Page 19 - This groove is separated by a narrow horizontal partition from a corresponding one on the superior face of the same element, and its surface is longitudinally roughened. The teeth are closely placed, and the series turns with the anterior extremity of the jaw, abruptly inwards. The transverse diameter of the teeth lessens to just posterior to the point of curvature, so that their section is nearly round; at and anterior to the curve, the wide transverse diameter is resumed, the FIG. 2.— Anterior...
Page 73 - ... of the existing Lacertilia, and it has a greater transverse diameter than the middle brain inferior to it. Its posterior border is at right angles to the line continued forwards from the superior border of the medulla oblongata at the foramen magnum. At its posterior base a flat horizontal process, as wide as the brain at this point, extends posteriorly in a corresponding fossa of the superior cranial wall. Its posterior margin occupies a transverse groove of the superior wall, between the superior...
Page 76 - I have termed the inferior reversed wedge, below. This arrangement accomplishes the purpose effected by the zygosphenal articulation, that is the strengthening of the articulation between the neural arches, but in a different way. The additional articulation is placed at the opposite extremity of the vertebra, and it is the anterior zygapophysis instead of the posterior one which is embraced. This structure entitles the genera which possess it to family rank...
Page 74 - It does not appear to be homologous with the recessus labyrinthi, since that cavity is not perforated by the fenestra ovalis. It appears to be a prolongation outwards of the vestibule and sacculus, which may be observed in a less degree in the genus Edaphosaurus (Cope), also from the Texas Permian formation. Here the adjacent bones are produced slightly outwards, and the fenestra ovalis is closed by a large stapes similar in external form to the one I have described in the...
Page 66 - Not determinable. NOTE. Since the manuscript of this article has been placed in proof two articles have appeared from the pen of Prof. SW Williston: 1. Restoration of Seymouria baylorensis Broili, an American Cotylosaur. Journal of Geology, vol. xix, 1911, pp. 232-237. 2. A new family of reptiles from the Permian of New Mexico. American Journal of Science, vol. xxxi, 1911, pp. 378-398. In the first of these the author presents a restoration of Seymouria and discusses its habits. The family name Seymourida...
Page 52 - ... as in most of the species of Pariotichus. The internareal and interorbital regions are flat. The narrower brain case is continued between the orbits, and its lateral walls are robust. The palatine bones extend from the maxillaries, and approximate each other nearly on the median line, where they are separated medially by a groove, which becomes wider posteriorly. No teeth can be discerned in the specimen, excepting the large anterior one already mentioned. The surface of the bone is, however,...
Page 46 - The elongate maxillary tooth is placed exactly half-way between the borders of the orbit and the nostril, which is posterior to its position in the P. aguti. The other maxillary teeth are small in comparison with the size of the skull. The enlarged anterior premaxillary teeth are not well preserved, and their size is uncertain. In some other specimens of similar size with rounded cross section of the muzzle, these teeth are enlarged as in P. aguti.

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