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Carnivorous Saurischia in Europe Since the Triassic 1

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Carnivorous Saurischia in Europe Since the Triassic 1 BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA VOL. 34. PP. 449-458 SEPTEMBER 30. 1923 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY CARNIVOROUS SAURISCHIA IN EUROPE SINCE THE TRIASSIC 1 BY F. VON HUENE (Presented before the Paleontological Society December SO, 1922) CONTENTS Page Introduction........................................ ........................................ 449 Specimens from Lower Lias and Lower Oolite of England 450 Specimens from France.............................................................. 453 Habits of the Megalosauridse............................................:... 457 I ntroduction In the Jurassic and Cretaceous of England, and France particularly, but also in several other countries, many skeletons, and principally frag­ ments of such, have been found, only a few of which have hitherto been described and named. Many of these remains have been referred to in the literature as Megalosaurus bucklandi. At present without special studies it is scarcely possible to ascertain what is meant by this term. Therefore I think it may be desirable to publish my studies on all of these forms, made in recent years in many museums of England, France and other parts of Europe, and in America, together with what is known from the literature. Two years ago in another place (“Williston Memorial Volume,” not yet published) I assembled and enumerated all these specimens. I found ninety-seven in Europe and fifteen in other parts of the world except North America, but not all of them were useful for accurate determina­ tion and comparison. The type specimens I have redescribed from my own observation and I have figured some and made restorations of a few of them. Several new species and even new genera have also been ' described. 1 Manuscript received by the Secretary of the Society March 15, 1023. XXX—B u l l . G e o l . S o c . Am., V o l . 34. 1922 ( 449) Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/34/3/449/3414518/BUL34_3-0449.pdf by guest on 25 September 2021 450 F. VON HUENE— CARNIVOROUS SATJRISCHIA IN EUROPE S p e c im e n s f r o m L o w e r L ia s a n d L o w e r O o l it e o f E n g l a n d In the English Lower Lias and in the Lower Oolite there are forms which, while closely related to the genus Megalosaurus, yet do not really belong to it, since they lie somewhere between Teratosaurus and Megalo­ saurus. For the present I shall not assign a name to this genus. The tibia of these specimens is characterized by a rudimentary crista lateralis at the lateral side of the proximal end and below its head. In Terato­ saurus this crest is still missing and in Megalosaurus it is strongly de­ veloped. The species from the Parker collection (Oxford) from Nether- comb (Humphriesi horizon of the Lower Oolite) I have named “Megalo­ saurus” nether comb ensis n. sp. Its pubis is rodlike in the distal (anterior) portion. The teeth are similar to those of the true Megalo­ saurus buchlandi, but, among other differences, are somewhat thicker than in that species. The true Megalosaurus buchlandi occurs only in the Stonesfield slate just below the Great Oolitic. So much of the skull is preserved that a restoration, within certain limits of error, is possible. This skull ex­ hibits some resemblance to Antrodemus. The cervical vertebrae are high, relatively short, and opisthocoelous. Neither the cervical nor the dorsal vertebrae show the pleurocentral excavations so sharply circumscribed or so deep as in Streptospondylus or in Antrodemus. The number of pre- sacral vertebrae is not known, but there is no valid reason why it should differ from that in Streptospondylus cuvieri, which has nine cervical and fourteen dorsal vertebras. The dorsal vertebras show only pleurocentral depressions, but not cavities. Below the diapophysis are strong support­ ing buttresses, with deep niches between them. The neural process is broad and thick, but not very high. The sacrum, as is well known, con­ sists of five vertebra. The anterior caudal vertebrae are as long as the dorsals. The hasmapophyses are like those in Antrodemus. The scapula is long, slender, and straight, as in Antrodemus, and its processus del- toideus is very high. The humerus, which is robust, is about half the length of the femur and a little more than half the length of the scapula. The ulna and radius are scarcely more than half as long as the humerus and are extraordinarily stout. Unfortunately the manus is not known. In.the pelvis the pubis is a narrow and distally rodlike bone, but is not completely known. The proximal expansion containing the obturator foramen disappears within a short distance of the proximal end. The ischium exhibits an angle in the middle of the shaft. The ilium is rather large and has a broad anterior spine. The trochanter major on the femur is a broad fanlike crest for the ilio femoral muscle, corresponding there­ Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/34/3/449/3414518/BUL34_3-0449.pdf by guest on 25 September 2021 SPECIMENS FROM LOWER LIAS AND LOWER OOLITE OF ENGLAND 451 fore with the large spina iliaca anterior. The distal condyles of the femur are separated by a broad groove even on the dorsal side. The tibia has a typical lateral crest near its proximal extremity. In the metatarsus a fifth metatarsal is not known and probably did not exist, so the pes stands between Teratosaurus and Antrodemus. Deslongchamp’s Poikilopleuron buchlmdi, from the Middle Dogger of Normandy, is only a rather large Megalosaurus, probably of the same group as M. buchlandi at Stonesfield. Since the specific name of these certainly different species would now be the same, the latter might better be called Megalosaurus poikilopleuron. The bone which I had mistaken some time ago for a pubis is rather a scapula. As a pubis its dimensions should be double. Therefore my former conclusions made from the form of the “pubis” are invalid. Of considerable interest is the fore limb with the manus. The humerus is very stout. Its length I should estimate, from a special study, as about half of the length of the tibia. The fore­ arm is extraordinarily short and heavy. The radius shows a prominent muscular process in the middle of its length. The manus has five fingers, as in the Triassic Plateosauridas, and differs from the later Carnosauria. The manus is relatively large. A very well known form from the Oxford clay is Megalosaurus (Streptospondylus) cuvieri, found in England and in Normandy. The best skeleton existing is that from Wolvercot in the Parker collection (Oxford), which I have studied in detail from Nopsca’s short descrip­ tions. The skull, much of which is rather complete, differs in some minor points from that of Megalosaurus buchlandi, of which much less is known. The importance of this specimen lies in the completeness of the vertebral series (nine cervicals,. fourteen dorsals, the first three sacrals, and twenty-nine caudals). The cervical and anterior dorsal ver­ tebras are deeply opisthoccelous, but this condition decreases posteriorly. Especially well developed are the neatly circumscribed pleurocoelous cavities, also decreasing toward the tail, but in the anterior dorsals they are still quite distinct, although soon becoming flattened. The cervicals are relatively short and high and the dorsals are relatively low. The sacral vertebras have saddle-shaped articular faces. The shoulder girdle is similar to that of Megalosaurus buchlandi. The humerus is less heavily built than in the latter form and has not half the length of the femur, or even of the tibia. The manus is relatively slender, but is in­ completely known. In the pelvis the ilium is much like that of Megalo­ saurus buchlandi and the same is true of the pubis, which has the medial lamella more developed in the proximal portion. The distal extremity Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/34/3/449/3414518/BUL34_3-0449.pdf by guest on 25 September 2021 on 25 September 2021 by guest Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/34/3/449/3414518/BUL34_3-0449.pdf 452 F. VON F. VON HUENE— CARNIVOROUS SAURISCHIA IN EUROPE F igure 1.—New Restoration of Megalosaurus (Streptospondylus) cuvien The restoration was made from Mr. Parker’s specimen. Oxford clay, Wolvercot, Dorsetshire. Corrected in a few points from the Paris specimen from Honfleur. The missing parts are dotted. One-sixtieth natural size. SPECIMENS EROM LOWER LIAS AND LOWER OOLITE OE ENGLAND 453 does not exhibit any hooklike thickening. The ischium differs from that of Megalosaurus buchlandi in having a rather straight shaft. The femur is less curved and the distal end is broader than in Megalosaurus buck- landi. The tibia has a well developed crista lateralis near its proximal extremity. The fibula is very slender. The form of the processus ascendens astragali resembles that of Megalosaurus poikilopleuron. The metatarsals and phalanges are much more slender than those of M. buck- landi. Although it is possible that a fifth toe once existed, there is now no indication of it. It is doubtful whether it is necessary to distinguish this species from the true Megalosaurus by a separate name (Strepto- spondylus). The reasons for doing so would be the deeper pleurocoelous cavities and the slenderness and certain minor characters of the skull. Another Megalosaurus from the Oxford clay of Weymouth (Dorset­ shire) in the Parker collection I call M. parkeri. This specimen is char­ acterized by high dorsal spines, an ilium differing in form from that of M. bucklandi, a very narrow pubis with large obturator foramen and a thick, hooked distal end, an ischium with lateral longitudinal ridge near the articular face, and a tibia whose ciiemial crest projects greatly for­ ward.
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