A NEW DINOSAUR. 
137 
Affinities. — Matley (1931, p. 281), 1 in commenting on the connexion 
in Mesozoic times of South America with south-eastern Asia by way of 
Antarctis, the Australian region and the Sunda Archipelago, as discussed by 
von Huene, says that it is i; really remarkable that all the three Cretaceous 
sauropod genera of India — Titanoaaurm, Antarciosawrus, and Laplahtsavrus — 
should be found so far away as Patagonia,” &c. Notwithstanding the wide 
range of these and other sauropodous genera, it is difficult to place this 
Queensland Cretaceous Dinosaur with any well-known types, in so far as com- 
parisons can be made with our material. Austrosaurus does not closely resemble 
any of the species described by von Huene 2 in his comprehensive work “ Los 
Saurisquios y Ornitisquios del Cretaceo Argentino,”- and it evidently does not 
belong to the Family Titanosauridse. 
Austrosaurm rnclillopi appears to be a more specialized Dinosaur than 
the Queensland Jurassic Sauropod RhaetoSaurus brownei , described by the 
writer. 3 In Austrosaurus the centra of the dorsal vertebrae attain a maximum 
of specialization in the intramural complex of laminae enclosing irregular 
cavities, supplementing the actual recesses of the pleurocceles. It is not clear 
whether the pleurocceles are actually connected with the complex of small 
internal cavities. Judging from the condition of the matrix, however, they 
were not, and probably only the lateral recesses were actually pneumatic in 
life. Owen’s view 4 that the inner recesses of such centra were filled with 
" chondrine,” although opposed by Seeley and Hulke, 5 6 may well be true. 
Apparently there are two types of cavernous dorsal vertebrae in the 
Sauropodous Dinosaurs. In one type, the lateral cavities or pleurocceles extend 
into the intramural area and form an enlarged chamber, recessed behind the 
actual opening : there is no complex of small cavities and the additional 
required strength of the centrum is formed by thick portions of the peripheral 
walls and a median vertical partition. 
This type of vertebra is illustrated by the transverse section of the 
trunk centrum of " Omilhopsie ” figured by Hulke in 1879,° here reproduced 
(Text-figure 2). The section of a dorsal vertebra of Marsh's Moromurua lentus 
(Camarasaurus, Cope) illustrates another development of this type, 7 and many 
other examples are known. Osborn and Mook record (lor. cAt., 1921, p. 306) 
that in Camarasaurus the pleurocceles “ occupy most of the bodies of the 
centra.” 
'Matley, C. A., Geol. Mag., Vol. LXVIII, 1931. 
2 Huene, F. von, Anales del Museo de La Plata, tomo III, serie 2, 1929. 
3 Longman, H. A., Mem. Qld. Mus., VIII, pt. 3. pp. 183-194, Plates XXIX-XXXIII ; 
Mem. Qld. Mus., IX, pp. 1-18, Plates I-V ; Australian Museum Mag., Vol. Ill, Xo. 3, 
pp. 97-102 ; Mem. Qld. Mils., IX, pt. 3, p. 249, Plate XXIX. 
4 Owen, R., Mon. Foss. Rept. Weald. & Purb., Supp. No. VI, 1874, p. 0. 
5 Owen, R., Quart. Journ. Geol. Soe„ vol. 35, 1879, p. 762. 
6 Hulke, J. W., Quart. Journ. Geol. Soc., 1879, Vol. 35, p. 756. 
7 Marsh, O. C., The Dinosaurs of North America, 16th Ann. Rep. U. S. Geol. Sur., 
1896, Plate XXXII, 6g. 2a. 
