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Show 766 DR. J. HECTOR ON CNEMIORNIS CALCITRANS. [Dec. 2, The frontal bone (11) is slightly swollen at the vertex, and depressed between the orbits, which have strong overhanging orbital processes, on which are rough, deeply impressed areas (Plate L X V I I . d), which probably gave attachment to a posterior excrescence of the cere as in Plectopterus, these impressions being separated by a smooth groove with only a faint mesial ridge. There appears to have been a deep notch (d) iu the upper part of the orbital border; but, the lachrymal bones having been lost, this is not very certain. The width of the nasal suture is equal to the length of the attachment of the lachrymals, which extends from the groove to the transverse suture (g). The interorbital septum is complete; and there are well-ossified rhinal chambers, with very minute olfactory foramina that proceed direct from the cranial cavity. The roof of the orbit is flat, with a very slight glandular groove. The optic foramen is at the posterior and inner angle of the orbit, directly above the front of the basipterygoid facet. Behind the postorbital process is a deep imperforate pit. The brain-cavity extends six lines anterior to the optic foramen. The upper mandible has all its elements completely fused; the large nostrils (Plate LXVII. fig. 1, e) occupy more than half the superior sloping area, their aperture being directed outwards, forwards, and upwards, rounded in front and angled behind ; and they are separated by a smooth bony interspace (f), which is one fourth the width of the mandible. The tip is rounded, with a tumid area for the attachment of the horny mandible, the length of which is equal to its width. Interiorly the palatal plate is flat, with deeply incurved borders, notched on each side of the tip ; but it is deeply excavated by a longitudinal groove (Plate L X V I I . fig. 2, h) which is perforated by two well-defined apertures, the one (h!) large and directed upwards, and the other (h") small, directed backwards in a line with the groove. The palatines are firmly united posteriorly with the vomer, the upper surface of which has a slight groove to receive the prsesphenoid. The lower mandible (Plate L X V I . fig. 2) is stout, but broad and compressed in every part, the rami preserving a lamellate structure throughout, and being united by a broad symphysis, the length of which is equal to one fourth of the mandible, the anterior half being flat and the posterior excavated. Inferiorly the punctate surface of the attachment of the horny mandible covers the whole of the symphysial portion. Pelvis. This bone agrees with Professor Owen's description so far as his imperfect specimen enabled him to fix its characters; but the complete preservation of the bone obtained from the Earnscleugh Cave enables m e to add the following:- The neck of the ischium is compressed to form the inferior notch, which is 9 lines in diameter, and contracted posteriorly to 5 lines. The ischium then expands to 8 lines, with a concave external surface, |