28 CHELTENHAM COLLEGE NATURAL HISTORY SOCIETY, 
poses,—to seek honey or eat pollen. The Co/eoptera (beetles) and 
Diptera (flies) visit them in great numbers, but as a rule they are not 
specialised for the purpose. Their proboscises are short and unde- 
veloped (not more than 2 m.m. long), and they are easily baffled in 
their search if it presents any difficulties, such as the concealment of 
pollen or honey in tubes. 
The Aymenoptera (Bee family) and Lepidoptera (Butterflies and 
Moths) on the other hand depend mainly on flowers for their subsist- 
ence, and show all grades of adaptation for the purpose. It may be 
worth while to touch upon some of these adaptations The simplest 
bees (e.g. Prosopis) are burrowing insects, and live in sand. Their 
bodies are for the most part smooth, and the tibie of their hind legs 
are furnished with two sharp spurs which help in digging. Their 
tongues are comparatively short, and have a spade-like termination for 
the same purpose. The AZacropts has a larger tongue, and exceedingly 
hairy legs, on which honey can easily be collected. In Sombus the 
tibial and tarsal hairs are better arranged, so as to serve as collecting 
baskets, and their tongue has developed into a marvellous set of sur- 
gical instruments, for sucking, gathering pollen, or piercing tissue. It 
attains a length of 21 m.m. in Sombus Hortorum, but by a perfect 
system of hinges, can still be withdrawn under the projecting spout. 
In Apis (the honey bee) the hairs of the leg are arranged in rows to 
suit its mode of collecting pollen moistened with honey, and the now 
useless tibial spurs have disappeared. The Lepidoptera have probos- 
cises, which sometimes attain the extraordinary length of 80 m.m, 
(3in.) which can be rolled up into spirals and put away when not in 
use. 
For purposes of research, a knowledge of the names of flowers and 
insects is all that is necessary. Asa beginner I have found Watts’ 
School Flora, and Bentham’s illustrations a useful combination for 
identifying flowers, and for general purposes Hooker is excellent. With 
regard to the insects I cannot offer any advice, and would be glad to 
know of the best simple books on the subject. 
So much by way of introduction. And now let us ask the question 
which gives the key-note of the subject, ‘ How can flowers afford to 
spend so much of their energy in cultivating beautiful petals, and in 
making honey? Sprengel, a German botanist of the last century, was 
the first to attempt to answer it, and to say that flowers arrayed them- 
selves so brightly to attract insects. The use of flowers to insects has 
been recognised from time immemorial, but here was the first distinct 
recognition of the complementary fact. The first flower to be exam- 
