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The Senses of the Lower Animals. 
[July, 
becomes vastly greater when we cross the “ Rubicon ” of a 
certain learned, but unbiological, professor, and strive to 
form some notion of the world as it appears to the lower 
animals. Have they the same senses as ourselves ? At 
the first glance the educated public will be disposed to 
assume that all living beings must as a matter of course be 
able to see, hear, smell, taste, and feel just as we do, and 
equally of course must possess no inlet of knowledge to 
which we are strangers. Closer examination, however, will 
throw doubts on both members of this proposition. Many 
animals are blind, not incidentally from disease or accident, 
but normally, the eyes being sometimes covered over with 
opaque membranes, sometimes merely rudimentary, and 
sometimes even totally wanting, the very optic nerve itself 
being obliterated. Such arrests of development occur in 
almost every department of the animal kingdom, even 
among the mammalia. Two species of mole are not figu- 
ratively but absolutely blind, Talpa cceca , found in Southern 
Europe, and the golden mole of the Cape of Good Hope 
( Chrysochloris inaurata). A rodent found in the eastern parts 
of Europe ( Spalax typhlus) has eyes so small, so deeply 
buried in its head, and furnished with so narrow an aper- 
ture, that it may be regarded as blind, functionally if not 
structurally. In the caverns of Kentucky two sightless 
rats and two bats equally deficient are said to occur, though 
whether they are totally^ blind is somewhat doubtful. No 
blind bird has hitherto been discovered, but amongst 
amphibians the renowned Proteus anguinus, found in subter- 
ranean pools in the caverns of Carinthia, is a signal instance 
in point. Two blind fishes have also been detected, one of 
which, Amhlyopus ccecus , is peculiar to the Mammoth Cave 
of Kentucky. 
The other senses proper to man seem to be shared at 
least by all the Vertebrata. They possess organs which are 
the homologues of our own, and which in most cases evi- 
dently discharge the same function. One exception on the 
large scale must not be overlooked. If we consider that 
smell bears upon substances either themselves aeriform or 
suspended in air, whilst taste relates to bodies either liquid 
or capable of solution in liquids, we can scarcely see how 
smell as differentiated from taste can exist in animals which 
are always immersed in water, and which respire through 
gills. With the exceptions thus pointed out, that of blind- 
ness in certain species and of scentlessness* in fishes, the 
* We want a word here. The one we use on compulsion might mean not 
only the inability to perceive odours, but the non-emission of any smell. 
