MOTIONS OF INSECTS. 275 



stercorarins), and also another, probably of the Tipu- 

 larian tribe (found by De Geer in a subputrescent stalk 

 of Angelica which he was unable to trace to the fly), 

 have each a fleshy leg on the underside of the first seg- 

 ment, which points towards the head and assists them in 

 their motions^. — Others again go a little further, and 

 are supported at their- anterior extremity by a pair of 

 spurious legs. An aquatic larva of a most singular form, 

 and of the same tribe, figured by Reaumur, is thus cir- 

 cumstanced. In this case the processes in question pro- 

 ceed from the head, and are armed with claws". Would 

 you think it — another Tipularian grub is distinguished 

 by three legs of this kind ? It was first noticed by De 

 Geer under the name of Tipda jnaculata {Tanypus 

 monilis, Meig.), who gives the following account of its 

 motions and their organs : — It is found, he observes, 

 in the water of swampy places and in ditches, is not 

 bigger than a horse-hair, and about a quarter of an 

 inch in length. Its mode of swimming is like that of a 

 serpent, with an undulating motion of the body, and it 

 sometimes walks at the bottom of the water and upon 

 aquatic plants. The most remarkable part of it are its 

 legs, called by Latreille, but it should seem improperly, 

 tentacula. They resemble, by their length and rigidity, 

 wooden legrs. The anterior lejj is attached to the under- 

 side, but towards the head, of the first segment of the 

 body. It is long and cylindrical, placed perpendicularly 

 or obliquely, according to the different movements the 

 animal gives it, and terminates in two feet, armed at 

 their extremity by a coronet of long moveable hooks. 



" De Geer, vi. /. xxii. f. 15, i. t. xviii. f. 8,7). 

 'Reauni. v. /. vi. f. 5, mm. 



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