260 ANIMAL SKETCHES. CHAP. 



difficulties of interpretation. As said the Danish naturalist, 

 Fabricius, nearly 100 years ago, " Nothing in natural his- 

 tory is more abstruse and difficult than an accurate de- 

 scription of the senses of animals." And this abstruseness 

 and difficulty is the more keenly felt in studying creatures 

 so widely different from ourselves as the bee. Such an 

 insect would seem at first sight to be about as susceptible 

 to the delicacies of touch as an ancient armour-sheathed 

 knight. Head, thorax, abdomen, limbs all are ensheathed 

 in chitinous l armour. The bee has his skeleton outside. 

 As an American gentleman once observed in my hearing, 

 the main difference between an insect and a vertebrate is 

 this : " One is composed of flesh and bone, the other is 

 composed of skin and squash." The question is, how can 

 delicate impressions of touch be transmitted through the 

 tough dense skin so as to affect the sensitive " squash " 

 within ? If you will examine one of the feelers of the bee, 

 you will see that the surface is richly supplied with hairs. 

 It is by means of such sense-hairs 

 that the bee experiences a sensation 

 of touch. Each touch-hair is hollow ; 

 and within it is a protoplasmic fila- 

 ment containing, it would seem, 

 the delicate terminal threadlet of a 

 nerve. But there may be two or 

 three modifications of the touch- 

 hairs. 



That insects are possessed of a 

 sense of taste cannot be doubted. 



Even if the caterpillars which refuse to eat all but 

 one or two special herbs, or the races of blood-suckers 

 which seem to have individual and special tastes, are 



1 Chitin is the hard tough substance of which the external skeleton 

 of an insect is composed. 



