Henry Woodward — Dawn of Life on the Earth. 295 



both in size and numbers, so as to have caused this period to 

 be called "the age of Keptiles," the Mammalia were apparently 

 reduced to a few minute forms of Insectivorous Marsupials, 

 known to us only from a rare series of their lower jaws, dis- 

 covered in the Purbeck beds and Stonesfield slates, the largest of 

 which was no bigger than the living Oi:)ossum.' Yet in speaking 

 of the huge Eeptiles of the Old World, of whose colossal size we 

 gather a notion from the cases containing their bones in the British 

 Museum, and from the plaster restorations in the grounds of the 

 Crystal Palace at Sydenham, how apt we are to overlook the fact 

 that the largest animals of the present day far exceed in size those of 

 any previous epoch ! Where shall we find a fossil lizard, whether of the 

 land or sea, to vie with the great " Finner whale " of our own day ? 

 — hugest of beasts that live, or ever have lived, disporting his eighty 

 or ninety feet of bone, muscle, and blubber, with easy roll among the 

 waves, secure fi'om shipwreck in the stormiest sea. 



The great class of Mammalia then to which we belong not only 

 includes all the higher orders existing at the present day, but also 

 the largest living beings, for the huge fish-like Cetacea are true warm- 

 blooded air-breathers like ourselves, and are as assiduous in the care 

 of their young as is the tenderest human mother. 



In the Lias we meet with another type of extinct sea-lizard, the 

 Ichthyosaurus, the remains of which have been largely preserved in 

 England, especially at Lyme Regis, at Street, at Barrow-on-Soar, 

 and at Whitby. 



This is the most fish-like of the lizards of the Mesozoic period, and 

 must have been a veritable shark amidst the smaller fry, to judge by 

 his terrible jaws armed with hundreds of conical teeth. Indeed, the 

 contents of his stomach betray even a cannibal tendency, for when 

 an hungered, he seems occasionally to have stayed his appetite till 

 dinner-time with three or four baby Ichthyosaurs au naturel ! 



The great feature of the Mesozoic age was no doubt its Ammonites ; 

 but besides these it had a rich assemblage of Trigonics, a shell now 

 only found living on the coasts of Australia, of TerehratulcB and Bhyncho- 

 nellce, of Cidaridce, and of that beautiful form of Crinoid "the Brad- 

 ford Pear-enorinite " Apiocrinites Parldnsoni ; and, lastly, of King- 

 crabs and other Crustacea, with Dragon-flies and Cycadaceous plants. 

 In the Vertebrate classes it had its Chim^roid Sharks, with palatal 

 crushing teeth ; its Pycnodont fishes ; its Ichthyosauria, Plesiosawia, 

 Pterosauria, and Dinosauria ; its long-tailed birds ; its all but oldest 

 Mammals yet discovered. 



From this wonderful and rich display of life-forms we next pass 

 over a long series of dreary almost unfossiliferous red sands and 

 marls charged with gypsum and rock-salt, chiefly remarkable for the 

 scanty evidences of another lost Eeptilian order (the Labyrinthodon) , 

 helped out by abundance of foot-tracks of quadrupedal and bipedal 

 Reptiles, and some perhaps of Birds (?). Some exceedingly minute 

 teeth have also been obtained near Stuttgart, which are considered by 



* See Prof. Owen's Monograph on the Mesozoic Mammalia, Pal. Soc. 1871, 

 vol. xxiv. pi. i.-iv. 



