802 Marvels of the Universe 
It must have attained a 
length of seventy-five feet 
or more. Another was 
Clidastes, which was forty 
feet long; Platycarpus was 
another. The Tylosaurus, 
here depicted, was of about 
the same size as Clidastes, 
only not so slender and 
snake-like, Dr. S. W. 
Williston, who has of late 
years discovered and de- 
scribed most valuable 
specimens of these old sea- 
serpents, was fortunate 
enough to discover one 
specimen of a skeleton 
' complete in almost every 
. detail. Such good fortune 
is a rare thing, as all 
fossil-hunters know only 
too well. In the case of 
Tylosaurus now under con- 
sideration, Dr. Williston 
found an impression of 
Photo by] : = . [W.s. Berridge, F.Z.S. : ; 
THE MIDWIFE TOAD. the skin near one of the 
The Toad is an inhabitant of France and Southern Europe. It is the male Toad which paddles, showing small 
cares for the eggs, carrying them about with him in the manner shown above. scales, rather like those of 
a snake. In Western Kansas a great many specimens have been found, showing that these 
reptiles flourished exceedingly in the sea which covered that part of North America in the 
Cretaceous period. They doubtless played the part of whales in those days, during the “ Age 
of Reptiles,’ before the mammals had attained to the grandeur of their present exalted position. 
There were plenty of fishes to serve them as food, so doubtless they had a good time and multiplied 
over the earth. But their days could not be prolonged, for in the great march of upward progress, 
or evolution, higher types appeared on the scene, and so they were doomed to extinction. Our 
knowledge of this order of reptiles is greatly due to Professor Cope’s arduous labours. The accounts 
which he has given of his explorations and the great difficulties he encountered, are most 
interesting, and such as every geologist can appreciate. We in England, who visit clay-pits, quarries, 
railway cuttings, etc., during an afternoon walk, and return home at our leisure with a few small 
specimens in our pocket, or a bag on our back, can hardly realize how arduous must be the work of 
digging out the skeletons of such beasts as Tylosaurus, packing up the separate bones and trans- 
porting them for long distances. 
THE MIDWIFE TOAD 
BY R. LYDEKKER, F.R.S. 
Ir is a remarkable circumstance that while in some representatives of the great tribe of frogs and 
toads the care of the eggs, as in the case of the Surinam Toad (to which a special article is devoted), 
is confided to the female, who may develop special structural modification for their accommodation ; 
