26 R. 8. Lull — Dinosaurian Distribution. 



they are found in strata which v. Huene refers in each case to 

 the Dogger but at points far removed geographically, in Eng- 

 land, in Utah, and in Madagascar (v. Huene, 1909, p. 14). If 

 v. Huene is correct in his derivation of the group from the 

 Theropod genus Plateosaurus, I should look to this swamp- 

 land extending during the late Trias from England to Eastern 

 Germany, before alluded to (vide supra p. 21) as the place of 

 origin of the race. That they reached such remote places 

 before their very existence is indicated in our records points to 

 the incompleteness of the latter and good powers of migration 

 along the swamp and delta formations which fringed the con- 

 tinental shores. 



The Sauropoda are abundant in England from the Bathonian 

 (Dogger) to the Weal den, in France from the Bathonian until 

 the Aptian, and then, if Deperet (1899) is right, after a lapse 

 of time during which no Sauropoda left their records else- 

 where in the northern hemisphere, they appear again in the 

 form of Titanosaurus at Saint Chinian and Languedoc in 

 southern France in beds referable to the Daman — the very 

 close of the Cretaceous period! 



In America, with the exception of Dystrophwus of the 

 Dogger of Utah and an unnamed Sauropod reported by Gil- 

 more (1909, p. 300) from the Lakota (Aptian) of Buffalo Gap, 

 South Dakota, the Sauropoda are confined entirely to the Mor- 

 rison and its eastern equivalent, the basal Potomac, and in the 

 South, to the Trinity sandstones of Texas and Oklahoma. A 

 remarkable feature of the career of the American types is that, 

 with the exception of the ill-known DystrqphoBus, the most 

 generalized Haploeanthosaitrus and the most specialized 

 Diplodoctis have been found associated in the same quarry, 

 although Riggs (1904, p. 246) argues for Ilaplocanthosaurus 

 a terrestrial habitat, on account of the similarity in length of 

 fore and hind limb and the apparent inflexibility of the verte- 

 bral column ; while Diplodocus shows the highest degree of 

 aquatic adaptation known within the group. 



In the southern hemisphere one finds sauropod remains 

 from India across Madagascar and East Africa to Patagonia, 

 almost the entire length from East to West around the south 

 shore of the old Gondwana continent. There is, however, no 

 record of their occurrence in Australia, a piece of negative 

 evidence which can hardly be weighed heavily in view of the 

 meagerness of the known dinosaur remains in that quarter of 

 our globe. 



The principal southern genus is Titanosaurus (Lydekker 

 non Marsh), the remains of which are found also in the Eng- 

 lish Wealden. The beds wherein the southern Sauropods 

 are found are, curiously enough, Upper Cretaceous, probably 



