YOUNG OF THE MEDUSAE. 213 



preceding species by the possession of a sort of 

 skeleton or framework, also transparent, and of 

 a horny texture furnished with a plate, which, 

 when the animal comes to the surface, serves as a 

 sail, by which it is wafted onward. And more 

 wonderful still, by means of long blue appendages 

 which hang downwards from its body, this ani- 

 mated skiff can row itself onward, in the absence 

 of a breeze, or steer when going before the wind. 



Until very recently the mode in which the 

 young of the acalephse are produced was wholly 

 unknown, although much curiosity was naturally 

 felt on such an interesting subject. Discoveries, 

 however, have been within the last few years 

 made by several distinguished naturalists, which 

 greatly add to the interest with which they are 

 regarded. 



It appears that the medusa gives birth to a 

 multitude of minute bodies, gelatinous like itself, 

 and in shape somewhat oval, like the seeds or 

 sporules of some of the sea-weeds, and clothed 

 with cilia, or hairs, that by their vibration propel 

 them through the water. These buds, as they 

 have been appropriately called, after a little 

 while, fix themselves to some stationary object, 

 and soon undergo a rapid transformation. The 

 body, instead of retaining its oval form, becomes 

 elongated, growing like a plant from the point 

 by which it is attached, increasing in width at 

 its upper extremity. In this upper extremity a 

 mouth is soon formed, surrounded by four pro- 

 minences that soon become long tentacula, like 



P 3 



