DR. A SMITK WOODWARD OK ofay x9xo,

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distinguished, except by the number and arrangement of their pre- maxillary teeth, which appear to be constant for each genus. If the European genera of Megalosauria may be similarly' characterized, the skull from Minchinhampton belongs to 31eqalosatcrtcs itself, for the distinctive number of four premaxillary teeth has already been found both in the type species, 3f. btcclclandi,t from the same strati- graphical horizon, and in a specimen from the Oxford Clay'.' It cannot be referred to Ceratosatcrtcs, the only other Megalosaurian in which a nasal horn-oore has been observed, because in this genus there are not more than three premaxillary teeth.

If, however, the new skull be correctly assigned to Wegafosatcrtte, it is readilv distinguished from the only satisfactorily-deflned species, ilL bMc/o4ndi, by the .shape of the maxilla and more: especially by' the relatively small size and stoutness of the few anterior teeth in both jaws. It is also'comparatively small, though this feature may' perhaps be due to immaturity. Its dentition is scarcely comparable with the isolated teeth' from higher horizons which have received names; and no reference can be made to the. forms known only by limb-bones or vertebrate. I propose, therefore, that the specimen now described be regarded as the type of a new species, to be known as 3fegalosatcrue bradleyi, in honour of its discoverer.

EXPLAIN.TION OF PLATE XI1I.

[Skull and mandible of /t&galosatcrcce bradtel/i, sp. nov., from the Great Oolite,
Mluchiuhampton (Gloucestershire). Gollectiou of K Lewis 13radley, F.G.S.]
Fig, 1. Left side-view, two-thirds of the natural size. A., antorbital fossa;

iY.,ntcrial opening; O., orbit; T., lateral temporal vacuity; V., vacuity

in mandible; ag., ccngulcr; d., dentary; rcpt., ectopterygoid {f); b,„

bony horn-core; j., jugal; l., lachrymal; tree., mcucilla; tca., nasal;,

pttca., premaxillcc; pt., pterygoid {f); f j., quadrate-jugal; a, depression

or vacuity in antorbital fossa.

2. Third premaxillary tooth, twice the natural size.

Sa. Largest maxillary tooth, twice the natural size, with {3 b) serratione.

enlarged 7 ditcmeterh

4. Supposed hyoid bone, crushed and broken, two-thirds of the natural size.

Dxsctrssrors.

The shape of the left ramus of the mandible is completely shown,

but its hinder half is so much fractured that its constitution cannot be exactly determined. The very slender dentary bone (d.) tapers to a blunt point at the symphysis, where its four anterior teeth are relatjvely small. It gradually deepens in its hinder half, and its >-shaped sutural union with the angular (ag.) is distinct below the small oval vacuity (V.), which occurs behind it between the angular and surangnlar bones. On its outer face may be observed a sparse longitudinal series of large nutritive foramina, those in the hinder half being placed in a shallow groove which inclines upwards posteriorly. The coronoid region is the deepest part of the mandi- bular ramus, its maximum depth equalling a seventh of the total length; but its upper margin is only gently rounded (not raised into a process), and it rapidly tapers behind to the very low articulation for the quadrate bone.

Most of the teeth are well displayed, and, exhibit a tendency to replacement alternately, as in crocodiles. Those of the premaxilla are remarkable for their very small size, the height of the third or largest tooth not quite equalling half the height of the largest maxillary tooth. They are thick, round or oval in cross-section, very slightly recurved, and only compressed to a sharp edge behind, where they are regularly serrated to the base. Their outer face is marked by a few slight vertical fiutings, which are best seen in the third tooth (Pl. XIII, fig. 2). The fourth or hindmost premaxillary tooth is not exserted; but the other three are com- pletely in functional position, and gradually decrease in size forwards. The foremost tooth of the maxilla, which is seen in its broken socket, is as stout and small as the premaxillary teeth; but all the others of the series are much laterally compressed and recurved, with a sharp serrated edge behind and a blunter, more finely serrated edge in front. The largest teeth of the mouth are those within the front half of the maxilla; while those in the hinder half of the same bone rapidly become smaller, until tbe hind- most (shown only in impression) arc very short and broad. The three teeth preserved at the symphysial end of the mandible are as small as the premaxillary teeth opposed to them, and apparently similar; but the other teeth of the dentary, so far as shown, resemble the principal teeth of the maxilla in shape, and only difFer in being much smaller. A.ll thc serrations of the teeth (Pl. XIII, fig. 8b) are in regular series, blunt, and not inclined upwards.

On the rock below the mandible occurs the Iong and slender curved bone shown in Pl. XIII,flg. 4. Itis smooth,and only impressed by a shallow longitudinal groove near its thicker end. 3oth its ends areindefinite, as if originally cartilaginous. It is probably one of the hyoid elements, which have already been noticed by Marsh in Ceratosatct Ms.

As shown by the discoveries in North America, all the skulls of Megalosauria are remarkably similar, and it is difflcult to flnd. generic differences between them. In fact, they can scarcely be

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