PW MEM mT teh gk 
NATURE 
377 
THURSDAY, MARCH 20, 1873 
PERCEPTION AND INSTINCT IN THE LOWER 
ANIMALS 
A ea correspondence in these columns, called forth by 
the letters of Mr. Darwinand Dr. Huggins (NATURE, 
Feb. 13), may be counted among the many indications of 
the growing interest in psychology ; while at the same time 
it furnishes evidence of how far our knowledge of mind is 
behind most of the other sciences. Of the important points 
in the valuable letters of Mr. Darwin and Dr. Huggins we 
shall speak presently. But let us remark first on the 
minor and distinct question raised by Mr. Wallace. He 
says : “ The power many animals possess to find their way 
back over a road they have travelled blindfolded (shut up 
in a basket inside a coach, for example), has generally 
been considered to be an undoubted case of true instinct. 
But it seems to me that an animal so circumstanced will 
have its attention necessarily active, owing to its desire to 
get out of its confinement, and that by means of its most 
acute, and only available sense, it will take note of the 
successive odours of the way, which will leave on its mind 
a series of images as distinct and prominent as those 
we should receive by the sense of sight. The recur- 
rence of these odours in their proper inverse order—every 
house, ditch, field, and village having its own well-marked 
individuality—would make it an easy matter for the ani- 
mal in question to follow the identical route back, how- 
ever many turnings and cross-roads it may have followed.” 
The objections to this hypothesis, to which Prof. Robert- 
son has given his adhesion, are very serious. Let the 
scent of the dog be ever so acute, it is in many ways ill 
suited for supplying the kind of guidance required. A 
hound on the track of a hare has to follow a stream of the 
same scent. The association here is between the hare 
and the smell of the hare. Are not the associations of 
smell all of this kind? Is there any evidence that either 
_ in man or beast one smell ever coheres to another so as 
_ to render possible a memory of odours apart from the ob- 
_ jects that give them forth? We are not very certain about 
the facts which the theory is put forward to explain; they 
are, however, better authenticated than is the fundamental 
assumpticn involved in the explanation. But, for the sake of 
argument, let us grant that a dog shut up in a basket can, 
as the result of a simple experience, link together several 
_ thousand smells in an unbroken series ; say, the stink of 
a dung-hill is associated with the odour of sweet hay, this 
with the scent of a flock of sheep passed on the road, this 
again with the smell of a railway station to the right, and 
‘so on during a journey ofsixty or seventy miles. If it be 
solely by the aid of this memory of smells that the dog is 
to return to the place whence it was taken, it must needs 
_ make haste back. It will be too late if the sheep have 
changed their position on the road. Especially is it 
necessary that it should get home while the wind still 
continues to blow in the same direction, otherwise its land- 
marks will be all in confusion. One other difficulty : 
suppose the dog to have got into the fragrance of the 
_hay-field, which is perhaps forty acres in extent, how is 
it to find the dung-hill at the north-west corner? particu- 
larly if the wind be blowing the wrong way. Is it to 
scour round the ill-defined outskirts of the perfume until it 
No, 177—VOL, vu. 
4 
comes on the ill smell of the dung-hill? If we try to 
conceive in terms of vision (we can make nothing of it 
from our experiences of smell) such a memory of smells 
as the dog is supposed capable of acquiring, we must 
represent to ourselves the sensations of being carried 
through a series of differently coloured mists, which, while 
they prevent us from seeing objects, blend and shade into ~ 
one another. Insucha case, though we might remember 
that the red came after the yellow, how, having got into 
the red, should we know in what direction the yellow 
might be found? These are among the difficulties that 
have not, it appears to us, been sufficiently considered by 
Mr. Wallace and Prof. Robertson. 
But what are the facts to be explained? Such home- 
journeys of dogs as might, bya stretch of imagination, or 
perhaps more correctly, want of imagination, seem to be 
accounted for by the smell-hypothesis, rest only on a 
rather loose kind of evidence, which can be adduced 
quite as abundantly in support of performances to which 
this explanation can be in no way applicable. In return- 
ing home do dogs “follow the identical route” by which 
they were taken away? There is no evidence even of the 
second-hand, loose, hearsay description, that this ever 
happened in a single instance.* The general impression, 
on the contrary, is that they despise the windings of 
rivers, turnpikes, and railways, and make for their des- 
tination by the most direct route. For example, and to 
add one more to the thousands of stories, we may men- 
tion that since we sat down to write we have received a 
letter from a gentleman telling us that about fifty years 
ago his paternal grandfather, living at Quorn, near Derby, 
sent two hounds by coach to his maternal grandfather 
living at Liverpool. Two or three days after their arrival 
they absconded together ; inquiries were set on foot, and 
it is said they were seen swimming the Mersey at a point 
a little above Liverpool, where the river is of great width. 
They could be traced no farther, but after some time they 
made their appearance at Quorn, “foot-sore and in bad 
condition.” Again, sheep, pigeons, and other animals that 
have not the miraculous scent of the dog, are believed on 
as good authority to find their way home through strange 
regions and from equally long distances. 
Alluding to this class of alleged facts, Mr. Spalding, in 
the February number of Macmillan’s Magazine, ventured 
to favour the view that through all the turnings and 
windings of a long journey the creatures somehow retain 
a perception of the direction of the place from which they 
were taken, and he further ventured to think that a hint ofa 
similar faculty is to be found in some men. In this con- 
nection the facts with regard to savages would be most 
valuable. What Mr. Darwin calls the “trifling fact,” 
communicated in his letter of last week, namely that his 
horse, which had been sent from Kent, véé Yarmouth, to 
Freshwater Bay, in the Isle of Wight, on the first day 
that Mr. Darwin rode him eastward, was very unwilling 
to return towards his stable, that every time Mr. Darwin 
slackened the reins “ he turned sharply round and began 
to trot to the eastward by a little north, which was nearly 
in the direction of his home in Kent ;” this observation, 
together with the circumstance that with the fact before 
his eyes, Mr. Darwin’s “impression was that he somehow 
knew the direction whence he had been brought,” appears 
* See letter of “J. T.” p. 384. We have other letters to follow. 
x 
