140 



THE MIDDLE PAST. 



in the upper oolite, apparently marsupial in their structure, 

 and pointing to the wombats, bandicoots, and phalangers of 

 Australia as their nearest living analogues. From the num- 

 ber of these imbedded in a few square yards of a stratum 

 near Swanage in Dorsetshire, we may confidently look for- 

 ward to the discovery of many other mammalian forms 

 every condition of the period being favourable to the de- 

 velopment of such a fauna. 



Oolitic Mammals, natural size 1, Lower Jaw and Teeth of Phascolotherium ; 

 2, Of Triconodon ; 3, Of Plagiaulax. 



Such are the phases of oolitic life, and such the conditions 

 of sea and land, which its miscellaneous sediments seem to 

 imply. Continuous lands of ample area for the growth of 

 a varied flora, open free-flowing seas for an exuberant marine 

 fauna, gigantic estuaries and river plains for the amphibious 

 reptiles of the Weald, and over all a genial but periodically 

 interrupted climate. We have as yet no means of deter- 

 mining the universal climatology of the period, but over 

 the oolitic areas of the northern hemisphere the varying 

 rings of coniferous growth would seem to indicate seasonal 

 variations, while the prevailing aspect of the flora, the 

 abundance of land reptiles, and the presence of small mar- 

 supials, point to conditions of general warmth and periodic 

 drought, such as now obtain over the riverless plains of 



