CORALS AND CORAL LSLANDS. 



tum^ an American Acti- 

 nia occurring along the 

 coast of the United 

 States, north of New 

 York, the length of one 

 of the lasso-cells, ac- 

 cording to Dr. Leidy, 

 was about a 400th of 

 an inch, and the charac- 

 ter of the extended lasso 

 was much like that ot 

 figure 4. The lower 

 part of the lasso, for a 

 length \\ times or more 

 longer than the cell or 

 sheath, is usually thick- 

 ened, and sometimes 

 slender ly spindle- 

 shaped, while the rest is 

 an even slender thread ; 

 and the thickened part, 

 and sometimes all the 

 rest, as above shown, is 

 spirally wound by a 

 slender line, sometimes 

 elevated, set with short 

 hairs or bristles. The 

 thread-like portion may 

 be wanting or very short. 

 The lasso is often twenty 

 times as long as the cell 

 or sheath, and occasion- 

 ally forty times ; but if 

 the thread-like part is 

 absent, only one and a 

 half to two times. 

 A lasso cell once used 



