187S.J The Senses of the Lower Animals . 291 
vertebrates may be considered to see, hear, smell, taste, and 
feel. Along the so-called lateral line in fishes there appear 
to be arranged organs of sense, whose nature is not per- 
fectly understood, but which are possibly capable of being 
aCted upon by different kinds of undulations. Still, it 
would be an adt of most unscientific rashness to infer that 
they must see the world around them as we see it. Let us 
take the most highly-specialised of our senses, the one 
most precise and definite in its indications— our light-sense. 
We all know how widely it varies among individual men. 
Almost telescopic in the Red Indian on his prairies, the 
Arab on the deserts, or the sailor on the ocean,* accustomed 
perhaps, through many successive generations to scan the 
horizon for indications of game, for an enemy, or of an 
approaching tempest, it becomes nearly microscopic in cer- 
tain men of science and certain artizans constantly in the 
habit of scrutinising the most minute objects. It is said 
that Wollaston could write upon glass with a diamond 
characters which none of his friends could distinguish with 
the naked eye, but which, when examined with a good lens, 
were found to be beautifully distinct and regular. Nor does 
human eyesight differ merely in its range. Some men can 
discern objects clearly under a degree of illumination much 
more feeble than is requisite for others. Some again can 
deteCt the most minute variation in the shades of any 
colour, whilst to others, as Dalton and an eminent chemist 
and physicist now living, scarlet, green, and gray are all 
one.f If, then, such diversity prevails in the sense of sight 
* This last instance has latterly been called in question. 
f According to the Times of India , a phase of colour-blindness, or, at any 
rate, of incapacity to distinguish colours, is very common among the lower 
caste natives. “ Our natives cannot distinguish between blue and green. 
They apply the word lal to a variety of objedts we should describe as yellow 
and brown, and apply the generic epithet ‘ tambada,’ corresponding to 
Homer’s Chalkos, to all the bright red tints. Like Homer, they speak of the 
blue sea as black [Kola pani). They apply the word nila, dark blue, to a 
grey horse, and their notion of the colour of the sky, or Asmani rung , is a 
light grey. The subjedt can be readily tested by anyone by telling his 
‘ boy ’ or some less civilised native to choose a blue, red, or green book from 
a pile on the table. I have just tried a puttawallah with different coloured 
books. Between green and blue he cannot properly distinguish ; tambada 
he applies to vermillion, and the rainbow he protests is simply red or green. 
This is just what Mr. Gladstone says about the colour sense in Homer’s 
Greeks.” 
If, then, the colour-sense in man is of recent origin, and has made notable 
progress since the days of Homer, the question further arises as to the date 
of its development among the lower animals ? If the perception of colour 
was feeble among primeval animals their colouration must have been dull 
and sombre, on the hypothesis of sexual connedtion. Are the least splendidly 
coloured groups survivals of earlier days ? On this subjedt the “ stone-book ” 
U 2 
