12 WORMS. 



are only able to distinguish light from darkness, are 

 completely deaf, and have only the sense of touch well 

 developed. Notwithstanding these facts, they exhibit 

 a surprising degree of intelligence in plugging up the 

 openings of their holes or burrows. " They act in 

 nearly the same manner as would a man, who had to 

 close a cylindrical tube with different kinds of leaves, 

 petioles, triangles of paper, etc., for they commonly 

 seize such objects by their pointed ends." ..." They 

 do not act in the same unvarying manner in all cases, 

 as do most of the lower animals ; for instance, they do 

 not drag in leaves by their foot-stalks, unless the basal 

 part of the blade is as narrow as the apex, or narrower 

 than it." In conclusion, Darwin remarks, " It may be 

 doubted whether there are many other animals which 

 have played so important a part in the history of the 

 world as have these lowly-organized creatures." 



Nereis virens * is one of the commonest of marine 

 worms. It is found along our coast, burrowing in the 

 mud between tide- marks. Its color is a dull green, 

 tinged with red, and, like the earthworm, it is beauti- 

 fully iridescent. For class instruction, alcoholic speci- 

 mens may be used. We now use, in the laboratory of 

 the Boston Society of Natural History, specimens pre- 

 pared according to Semper's method by Mr. B. H. 

 Van Vleck, Assistant in the Museum, which leaves the 

 specimen dried, but in a state favorable for observing 

 the general anatomy and external characteristics. 



Upon examination, the pupils will observe that the 

 body of Nereis is much larger and longer than that of 



* A good figure of this species can he found in Morse's 

 " First Hook of Zoology," p. 83, Fig. 83. 



