ANIMAL REMAINS. 75 
form of Pterodactyles. The earth was probably 
at that time too much covered with water, and 
those portions of land which had emerged above 
the surface, were too frequently agitated by 
earthquakes, inundations, and atmospheric irre- 
gularities, to be extensively occupied by any 
higher order of quadrupeds than reptiles. 
As the history of these reptiles, and also that 
of the vegetable remains,* of the secondary for- 
ficient for the great purposes of the Creator, when the earth was 
rendered fit for the habitation of man. They do, indeed, afford 
the wandering savages of Australia a partial supply of food ; but 
it is more than doubtful that any of the species will be preserved 
by civilized man on the score of utility. The more valuable and 
tractable ruminants are already fast encroaching on the plains 
where the kangaroo was once the sole representative of the 
graminivorous Mammalia. 
" It is interesting, however, to observe, that the Marsupials, 
including the Monotremes, form a very complete series, adapted 
to the assimilation of every form of organic matter ; and, no 
doubt, with enough of instinctive precaution, to preserve them- 
selves from extermination, when surrounded with enemies of no 
higher intellectual powers than the Reptilia. It would, indeed, 
be a strong support to the consideration of them as a distinct 
ovoviviparous sub-class of Mammals, if they should be found, 
as hitherto, to be the sole representatives of the highest class 
of Vertebrata, in the secondary strata." — R. Owen. 
* The vegetable remains of the secondary strata differ from 
those of the transition period, and are very rarely accumulated 
into beds of valuable coal. The imperfect coal of the Cleveland 
Moorlands near Whitby, on the coast of Yorkshire, and that of 
Brora in the county of Sutherland, occurs in the lower region of 
the oolite formation ; that of Bllckeberg in Nassau, is in the 
lower region of the same formation, and is of superior quality. 
