276 THE SENSORIAL FUNCTIONS. 



takes the first opportunity of quitting the hive, never more 

 to return. A queen bee, thus mutilated, ran about, without 

 apparent object, as if in a state of delirium, and was incapa- 

 ble of directing her trunk with precision to the food which 

 was offered to her. Latreille relates that, having deprived 

 some labouring ants of their antennae, he replaced them near 

 the nest; but they wandered in all directions, as if bewil- 

 dered, and unconscious of what they were doing. Some of 

 their companions were seen to notice their distress: and, ap- 

 proaching them with apparent compassion, applied their 

 tongues to the wounds of the sufferers, and anointed them 

 with their saliva. This trait of sensibility was repeatedly 

 witnessed by Latreille, while watching their movements 

 with a magnifying glass. 



The Arachnida, from the mobility of their limbs, and the 

 thinness of their cutaneous investment, have a very delicate 

 sense of touch. Among the Mollusca, it is only the higher 

 orders of Cephalopoda that enjoy this sense in any con- 

 siderable degree, and they are enabled to exercise it by 

 means of their long and flexible tentacula. Many bivalve 

 mollusca have, indeed, a set of tentacula placed near the 

 mouth, but they are short, and of little power. It is pro- 

 bable that the foot may also be employed by these animals 

 as an organ of touch. 



Fishes are, in general, very ill-constructed for the exer- 

 cise of this sense; and their fins are used for no other pur- 

 poses than those of progressive motion. That part of the 

 surface which possesses the most acute feeling is the under- 

 side, where the integuments are the thinnest. The chief 

 seat of the sense of touch, however, is the lip, or end of the 

 snout, which is largely supplied with nerves; and perhaps 

 the cirrhi, or little vermiform processes called barbels, which 

 in some species are appended to the mouth, may be subser- 

 vient to this sense.* These processes in the Silurus glanis 

 are moved by particular muscles. 



* These kind of tentacula are remarkable for their length and mobility in 

 the Lophins piscalorius, or Angler; and it is said that they are employed by 



