18 Mr. Rennie on the Cleanliness of Animals. 



The instrument just described, accordingly, when expanded 

 over a portion of this shagreened surface, was subsequently 

 drawn out, with an evident effort, (repeated, if necessary,) 

 in the same way as boys draw their moist leather suckers, 

 when they amuse themselves in dragging stones after them. 

 Every particle of dust or other extraneous matter is thus 

 detached from the skin, and, by a peculiar movement of the 

 retractile rays, is lodged in the funnel-shaped pocket. 



Larv of the glow-worm on a tendrilled branch, using its cleaning instrument. 



This singular instrument is also used for the very different 

 purpose of assisting the animal to walk, and particularly to 

 maintain a position against gravity, which its feet are ill calcu- 

 lated to effect ; though its habits, as we shall presently see, 

 render it in some measure indispensable. 



Larva walking against gravity by means of the funnel at the anus. 



The interest which I began to take in the insect induced me 

 to endeavour to ascertain its species $ and on turning over the 



