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Show 782 MR. C W. ANDREWS ON A NEW BIRD [Julie 20, its widest point being at the antitrochanters (a.t.). The pelvic escutcheon narrows somewhat towards its posterior end ; in its middle line the neural spines of the sacral vertebrae form a slight ridge, on either side of which there are some traces of interosseous foramina, at least posteriorly, but these openings are not developed to anything like the degree seen in Phalacrocorax or Plotus. The line of junction of the postacetabular portion of the ilium with the synsacrum can be seen. Above the ischiadic foramen the ilia are very narrow and convex from side to side. Fig. 2. Pelvis of Prophaethon shrubsolei; partly restored from the opposite side. .Natural size. acet., acetabulum; a.t., antitrochanter; if., ischiadic foramen; it., ilium; is., ischium ; o.n., obturator notch ; pu., pubis ; s., sacrum. The ischia (is.)consist anteriorly of a narrow7bar convex externally; posteriorly they become greatly expanded and fuse with the ilia, closing a large ischiadic foramen (fig. 2, if), the shape of which is an irregular oval. The posterior angles of the ischia are broken away, but they seem to have extended backward and downward as in Sula. _ Of the pubes (pu.) only the proximal portion of that of the left side is preserved. The obturator notch (fig. 2, o.n.) remained open posteriorly, but there are indications of a blunt process on the ischium which at least partly closes it. Beneath and in front of the acetabulum, on the right side, there is a prominent knob of bone, which was at first mistaken for the pectineal process, but which is actually merely a fragment of bone, probably of the femur. There are remains of two or three ribs (r.), two of which emerge from beneath tbe ilia and probably articulated with the anterior synsacral vertebrae. The left femur (/.), lying in nearly its natural position with regard to the pelvis, is fairly well preserved except at its distal end. Unfortunately only its outer surface is visible, so that it supplies |