212 TKF. BOTTOM OF THE SEA. 



so frequently observed. Freyssinet and Turrel ob- 

 served, near the shores of Luzon, an extent of some 

 sixty millions of square yards coloured a bright 

 scarlet. This tint was owing to the presence of an 

 organisation so small that forty millions of individuals 

 occupied the space of a square millimetre.* As 

 the discoloration extended to a considerable depth, 

 it would be impossible to form even an approximate 

 idea of the number of living beings which caused it. 



Some of these microscopic creatures never develope 

 to anything beyond a little cell surrounded with vi- 

 bratory cilice, unequally distributed over the surface, 

 and serving the creature either as rowers or as an 

 organ for continually renewing the water which sur- 

 rounds it by creating a current. Their mode of 

 reproduction is extremely simple, and, at the same 

 time, admits of their propagation with almost frightful 

 rapidity. About the middle of the creature the body 

 contracts like the division between the two parts of 

 an insect, and the contraction increases until it 

 separates into two. Each part goes through the 

 same process as its parent, continually dividing into 

 new creatures, until in about twenty generations a 

 single infusoria may have engendered more than a 

 million. One generation succeeds another very 

 quickly. If, then, a variety of causes did not conspire 



* A millimotrc is OoDBTths of an inch. 



