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Rh the quadratojugal and contiguous parts of the jugal have suffered some abrasion it is possible that the separation of the jugal from the quadrate is less pronounced than shown in the ﬁgure. The postorbital process is very slender, and there is a very pronounced spur-like and somewhat elevated point ﬁtting into a recess at the suture with the frontal (prefrontal?). A deep pit occurs at the base of the upwardly directed process or separate triangular bone which we have considered, possibly at least, to be the prefrontal. Length from supero-posterior to infero-anterior point, 237 mm. Suture with quadratojugal, 95 mm.

Orbit—This aperture is oval with the greater diameter strongly inclined backwards from the line of the teeth; maximum length, 170 mm., maximum width, 105 mm.

Lateral temporal fossa—This vacuity is long and narrow: 195 mm. by 50 mm.

Quadrate—The quadrate is 280 mm. long and concave posteriorly. The external width at the upper end is 45 mm.; just above the suture with the quadratojugal it is 65 mm., and at the narrow part above the lower end, 40 mm. It is deeply excavated for the quadratojugal.

Quadratojugal—The visible part of this bone is very narrow: its height is 95 mm. and its maximum external width, 25 mm. As already stated it is somewhat doubtful if it entirely separates the jugal from the quadrate.

Squamosal and paraoccipital process—The squamosal forms a deep cotylus for the quadrate and sends down a long process at the rear of the lateral temporal fossa: it forms the external part of the paraoccipital process for two-thirds of its length, the rest of this structure being formed by the exoccipital as in other trachodonts.

Parietals—These bones meet in a narrow longitudinal edge between the supratemporal fossae for a length of about 50 mm. Anteriorly the superior margin turns abruptly upwards for 35 mm. to the inferior surface of the crest. Here the bones ﬂange outwards and backwards in overlapping sutures on the inferior surface of the frontals. Laterally they sweep around and form the anterior margins of