332 FUNCTIONS AND INSTINCTS 



of suction, though employed, perhaps, in extract- 

 ing the sap or the blood of plants, and at the 

 same time, in many respects, as we have lately 

 seen, they approach the polypes. 



The Flukes, likewise, appear to have some 

 characters in common with the leech, 1 so that 

 a passage is open from the intestinal worms 

 towards the Annelidans, some of which, as the 

 earth-worm, occasionally become intestinal, and 

 several are possessed of reproductive powers 

 almost as great as those of the pseudo-leech, 

 or the polype. I shall therefore next, in taking 

 my departure from the worms, bend my steps to 

 the animals just mentioned, which formerly bore 

 the same general denomination. 



They are called Annelidans, I suppose, 

 because they appear to be divided into little 

 rings, or else to have annular folds, and are 

 soft vermiform animals, some naked, others in- 

 habiting tubes, in some simply membranous, 

 in others covered with agglutinated particles of 

 sand, and in others formed, like those of the 

 Molluscans, of shelly matter. Some have nei- 

 ther head, eyes, nor antenna?, while others 

 are gifted with all these organs ; instead of 

 jointed legs, their locomotions are accomplished 

 by means of fleshy bristle-bearing retractile 

 protuberances or spurious legs disposed in 



1 See above, p. 325. 



