164 



REPRODUCTION. 



ally formed, the four corners (bf) become elongated, and, 

 by degrees, are transformed into tentacles, (c.) These 



a 







01 



Fig. 142. 



tentacles rapidly multiply, until the whole of the upper 

 margin is covered with them, (g.] Then transverse 

 wrinkles are seen on the body, at regular distances, ap- 

 pearing first above and extending downwards. These 

 wrinkles, which are at first very slight, grow deeper and 

 deeper, and, at the same time, the edge of each segment 

 begins to be serrated, so that the animal presents the ap- 

 pearance of a pine cone, surmounted by a tuft of tentacles, 

 (h ;) whence the name of Strobila, which was originally 

 given to it, before it was known to be only a transient state 

 of the jelly-fish. The separation constantly goes on, until at 

 last the divisions are united by only a very slender axis, and 

 resemble a pile of cups placed within each other, (i.) 

 The divisions are now ready for separation ; the upper ring 

 first disengages itself, and then the others in succession.* 

 Each segment (d) then continues its development by itself, 

 until it becomes a complete Medusa, (k ;) while, according 

 to recent researches, the basis or stalk .remains and pro- 

 duces a new colony. 



347. It is thus, by a series of metamorphoses, that the 

 little animal which, on leaving the egg, has the form of the 



* These free segments have been described as peculiar animals, under 

 the name of Ephyra. 



