94 A MANUAL 



I call them varieties of Actinia hellis. I collect a 

 group of animals (see Chapter III.) similarly differ- 

 ing among themselves, and call them varieties of 

 A. mesemhryanthemiim. Also another group (same 

 Chapter) varieties of A. coriacea. Lastly a group 

 (same Chapter), whose only difference is one of 

 colour also, which I am directed to divide into three 

 species, and call them respectively Actinia mvea, 

 venusta and aurora. 



Why should I act in this inconsistent manner ? 



That I cannot .answer. 



What reason have I for asserting that colour is 

 the distinctive mark of a variety, and form and habit 

 that of a species ? 



The fact is that we know next to nothing about 

 the state of sea-anemones at the creation. 



If we take a plant, and propagate it by seed for 

 several years, and it continue to bring forth similar 

 plants, in proportion to the length of time in which 

 it remains constant will be our certainty of its being 

 a species. If it alter, its former state will be the 

 form of a variety, and the alteration will be that of 

 the species, probably; and a number of similar 

 plants similarly altering will confirm our opinion. 



So, I cannot see any method of absolutely en- 

 suring the truth as to the species of sea-anemones, 

 except a like method of careful breeding and accurate 

 observation. 



But in tlie mean time wliat are we to say ? 



