Marvels of the Untverse 871 
beginning ; we must be content with a fragment or two bearing on the diabolical ingenuity with 
which Nature has fashioned the skull of the modern Crocodile, so as to enable it to drown its prey 
without discomfort, to say nothing of the risk of drowning itself. If the under-surface of the skull 
of a modern Crocodile be examined, it will be seen that the hinder passage of the nostrils, or 
“posterior nares,’ has been carried back to the extreme hinder end of the skull, while they open 
forwards at the extreme tip of the snout ;: so that the air necessary for breathing is brought right 
back to the very mouth 
of the windpipe in a closed 
tube. To further perfect 
the mechanism of breath- 
ing, the fleshy palate 
which forms the roof of 
the mouth sends down a 
tightly-fitting flap or fold, 
which fits on the tongue. 
Thus it is that the scaly 
monster is enabled _ to 
drown his victim, even 
though his own mouth is 
full of water; for he can 
breathe readily enough if 
once in a while he can 
manage to shove his snout 
just above the surface of 
the stream. We must 
suppose that Crocodiles 
throughout all the ages 
adopted a similar method ; 
but in their case the 
mechanism was far less 
perfect, since the bony 
tube leading to the back of 
the throat was conspicuous 
by its absence ; and this 
passage could have been 
formed only by fleshy 
membranes liable at any 
time to yield to pressure, 
and either admit water or 
close up the air-passage. 
This much the older fossils, 
such as we have already 
alluded to, show us. In 
all these, save the oldest, to 
be presently described, the 
[By Theo. Carreras. 
A SPIDER-HUNTING WASP. 
xs P It is the mother Wasp who is the hunter. When she has found a suitable spider she 
anterior nostrils opened stings it, and either paralyses or kills it; then she hangs it up out of harm’s way in the 
9 forked stem of some plant while she digs a burrow, into which she finally drags her victi 
ip of the snout 2 3 p YACTOe m, 
at ane t Ip Z Then, depositing an egg, she leaves it asa food-supply for the yet unhatched Wasp-grub. A 
as in their descendants section of one of the burrows is shown in the foreground. The species is known as the 
to-day ; but the posterior msde Wasp. 
