80 THE CILIARY CURRENTS. 



With a strong light behind the animal I distinctly 

 perceived a ciliary vibration down the interior of the 

 stomach, at least at the two sides when viewed trans- 

 versely. 



The septa are eight in number, but two in every 

 polype are destitute of the contorted threads ; which, 

 I am inclined to think, where present, run between 

 the sides of each septum, this consisting of two 

 membranes ; but of this I am not quite certain. 



The base of each polype does not rest like an inde- 

 pendent body on the surface of its cell, but springs 

 from the circumference of the cell, each polype-base 

 being actually contiguous to, and in fact continuous 

 with its surrounding neighbours. The polype-skin 

 is really a prolongation of the common integument 

 of the mass. 



Under a power of 220 diam. a living polype showed 

 a current along the pellucid skin ; minute globules 

 being carried both upwards and downwards with a 

 motion much like the circulation in Chara, &c. I 

 saw it most distinctly near the basal part of the ani- 

 mal, but whether it was within the substance of the 

 skin, or along the interior surface, I could not be 

 absolutely certain. It was a very different motion 

 from the close and rapid ciliary waves of the stomach, 

 which were plainly visible in the same animal. The 

 currents must, however, be in the cavity; for I 

 observed the globules follow the outline of one of the 

 tortuous threads, and also that of the angle of the 

 stomach, whence I must conclude that the whole of 

 the interior surface, as well as the various organs, is 

 covered with vibratile cilia of excessive tenuity. 



