ae which’ niles are Soden for, are the: senses. oat ere “and sme 10 
_ sense of smell of the insects, which are on so much lower a level th 
is developed to such perfection that we are unable to grasp it, especia 
; whose task it is to search for the female. _ : 
cavities with a sense papilla in ‘the centre, or simply such pape § le 
special hairs. Insects with a very strong sense of smell have many such cavities 
remarkably big feelers or, at any rate, feelers the surface of which is increase 
lamella or similar structures. The honey bee, e.g., has from 14000 to 15000. 
cavities and about 200 papillz on each feeler, the male cockchafer 39000, wh« 
window. The following experiment proves that in such a case exclusively the sen 
of smell is concerned: If the female is covered with a glass dish and then placed 
near the open window, but the box with sand, on which it had been kept so far, ‘in’ 
the middle of the room, the males will flutter past the female and as far as the sand 
on which it had been before. The males of certain moths, as may here be mentioned, 2 
sometimes try to join a female, kept permanently in a room of a house, by passi 
through the chimney and the fire-place. Such an extraordinary capability of the se 
of smell can only be explained, as it is used exclusively for this sole pupose, by t 
it is specially adjusted to the smell given off by the female and remains more or 1 
unaffected by other smells. At any rate, in this way, insects which live secluded 
occur but seldom will find one another with certainty, so fiat the maintenance of t 
species is secured. & 
In a similar way, the sense of smell and the own peculiar sei serve to h Id 
, together the communities of many mammals, It can easily be observed, with gregario 
animals, that if one has gone away or the whole community has been dispersed a 
all unite again within a short time. . 
: To what an extent animals living in the same Siawict are guided by their : sen: 
: of smell, even if they are not gregarious, is shown by their distinctly recognizab 
paths in the woods, by means of which they get from the feeding place to the resti 
place, from the thicket to the meadow, in short, to wherever others of their sind 
used to go. Similar paths can be traced on the fieids. If e.g. field mice have 1 
tiplied strongly, so that hundreds of their holes are to be found on- a comparat / 
small surface, all these holes are joined by a network of paths, due to ‘that one m 
always follows the trail of another. ; : : = 
Ro6rig further calls attention to the remarkable fact that animals which 2 ar 
of following a trail are able, when crossing any, to recognize the direction 
man or animal have moved, i.e. to the right or to the left. So far, af has 
possible to find a satisfactory solution of this question. : 
Many animals, which are not gregarious, have the tendency to make 
‘a known to other members of their species by a more lasting mean: 
a _ which disappears after some time and is, a rather uncertain. 
7 ON Say 4 wis. Ta a 7 
ae 
s z e 5 
aay 
