ZOOLOGY. 243 



roinai, mostly crowned with a double series of retractile 

 hooks. 



An extremely troublesome and injurious tribe, inhabiting 

 the intestines of Mankind, as also several species of Quadru- 

 peds arid Birds ; they are very tenacious of life, and are 

 reproduced from parts or joints that accidentally become 

 detached. 



1 5. Furia. Body linear, ciliated on each side with reflect- 



ed appressed prickles. 



** JSot inhabiting other Animals. 



16. Gordius. Hair- Worm. Body equal, filiform, round 



and smooth. 



17. Hirudo. Leech. Body truncate at each extremity; 

 head and tail dilated when ia motion. 



*** Not inhabiting other Animals^ but furnished with a 

 lateral pore. 



18. Lumbricus. Dew, or Eartii-Worm. Body round, an- 

 nulated, furnished with minute concealed jprzc We*. 



19. Siphunculus. Tube- Worm. J3oc/y round ; mouth cylin- 

 drical, and narrower than the head, aperture on the side. 



20. Planaria. Body gelatinous, depressed, with a double 

 ventral ^ore. 



R 2 



