770 Extracts from the Minute-Book of the Linnean Society. 



flexible and extensile, and, either separately or collec- 

 tively, can be protruded beyond the caudal segment, 

 or retracted within it, at the pleasure of the animal. 

 Their efficiency as a cleaning apparatus, and an organ 

 of adhesion and progression, depends principally upon 

 the mucus they emit, which is secreted in great abun- 

 dance, and not upon the power of producing a vacuum. 

 When this instrument is applied to the body of the 

 insect, any extraneous matter immediately becomes 

 attached to it, and the impurities thus collected are 

 ultimately expelled by a fresh discharge of mucus and 

 a peculiar motion of the papillae." 



Catalogue 



