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MANUAL OF ZOOLOGY 



band. The cilia of each row are cemented together at 

 their bases, free from one another distally, so that each row 

 is comb-shaped, the basal cemented parts of the cilia 

 forming the back of the comb, the free portions the teeth. 

 It is by the paddling action of the numerous swimming 



mth. 



Fig. 65.— Hormiphora (Cydippe) plumosa. A, from the side; B, from the aboral 

 pole, mth, mouth; s. pi, swimming plates; t and 6, tentacles. Natural size. 

 ■ Mediterranean Sea. (After Chun.) 



combs of these eight bands that the ctenophore is propelled 

 through the water. 



Laterally there is situated a pair of long slender tentacles, 

 each provided with numerous little tag-like processes, and 

 having its base lodged in a sheath into the interior of which 

 the whole tentacle can be retracted. At one pole, the oral, 

 is an opening, the mouth : and at the opposite pole is 

 a pair of minute pores, the excretory pores, which are the 



