ANIMAL INTELLIGENCE. 27 
following instance of novel behaviour on the part of humble 
bees seems to indicate progressive intelligence. 
It is many years since I first noticed that the blossoms 
of the blue sage (Salvia patens) in my garden in Scotland 
had all been bitten across the throat just above the stiff 
calyx. Upon examining flowers of the same species in a 
Berkshire garden, I found that they were intact, though 
there were plenty of humble bees about, and so were those 
in a Scottish garden not twenty miles from my own. Now 
this sage is a native of Mexico, and possesses a beautiful 
structure to secure cross-fertilisation. The beak of a hum- 
ming-bird or the proboscis of a moth, inserted into the tube 
of the flower, presses on a lever which causes the anthers to 
descend from their position in the upper lobe of the corolla 
in such a manner as to deposit upon the bird’s head or 
insect’s back a mass of yellow pollen, part of which is sure 
to adhere to the stigma of the next flower visited. The 
honey glands of the sage are very productive, but the tube 
of the flower is narrow and difficult, prohibiting the passage 
of our substantial bumble bees. My suspicion fell upon 
these as the burglars, although they were equally plentiful 
in all the three gardens referred to, and the flowers had only 
been injured in one of them, because I had already observed 
that the bumbles treated the long spurs of yellow toadflax 
in similar unscrupulous fashion. My suspicion was con- 
firmed by detecting a bumble in the act upon a blue salvia. 
It may be objected that, after all, here is evidence, not 
so much of intelligence as of a keen scent for honey and a 
sharp pair of jaws. Quite so; but then why has the practice 
not become universal in the bees of all gardens? Moreover, 
in the summer of 1902, I found that the bumbles in my own 
garden had improved upon their earlier practice. For 
several years, the incision was made at the front of the 
throat of the flower, where the diameter of the tube is 
greatest. It seems to have dawned upon the bees that the 
shortest way is the best, because now they invariably bite 
through the side of the tube where the diameter is smallest. 
Yet in all the years that have elapsed since the introduction 
of the blue sage from Mexico, it is only some bumble bees 
