76 Dwellers of the Sea and Shore 



and gauzy plumes elongate, they trail behind the swim- 

 ming animal In graceful undulating curves until they 

 reach the amazing length of twenty or more times the 

 diameter of the body. 



At one pole of Its body is the mouth, a narrow, slit- 

 like opening; at the other is a small area In the center 

 of which is the so-called "eyespot." This eye, however, 

 cannot see as the fullest meaning of the word would 

 imply, being sensitive only to light and darkness. Yet, 

 notwithstanding, it seems to be aware of the approach 

 of danger, for often the presence of a moving boat or 

 other commotion In its neighborhood will cause it to 

 disappear toward the bottom. 



Now it will be noted that in the two forms just 

 reviewed, the motor appendages, or cilia, by means of 

 which they swim, are arranged in eight rows. In all 

 ctenophores these rows run in a direction with the longi- 

 tudinal axis of the body, and It is from their fancied 

 resemblance to combs that the early observers assigned 

 to the members of the entire class the term "comb 

 jellies"; hence, their systematic name Ctenophora, or 

 comb bearers. But, although the comb jellies are easily 

 recognizable by virtue of their swimming organs, this 

 distinction is, after all, a very superficial one. They 

 are classed apart from the true jellylishes, or Scyphozoa, 

 because of other very real and far more fundamental 

 differences. Besides the fact that both sexes are united 

 in one individual, the comb jellies may be said to differ 

 from the jellyfishes chiefly in their method of reproduc- 

 tion, which Is to say, their eggs hatch directly into free- 

 swimming young who in appearance or habits are in no 

 essential respect unlike the adults. That this Is not so 



