THE AMERICAN BOTANIST 31 



different in value. There are, first of all, the variations prop- 

 erly classed as freaks and not to be included with regular varia- 

 tions. Of true varieties there are varieties due to geographical 

 position, edaphic forms due to soil conditions, forms due to 

 varying life cycles, such as annual forms of perennial species, 

 seasonal forms due to temperature, elementary species and 

 various color forms. There are also juvenile forms and per- 

 haps others. Tlie longer we study plants, the more there ap- 

 pears still to be learned about them. 



De;cadent Species. — An immense number of plants and 

 animals have appeared on the earth and, after an existence ex- 

 tending over perhaps a million years, have declined and disap- 

 peared. We commonly assume the extinction ^f such forms 

 to be due to untoward circumstances, such as sudden and ex- 

 treme changes of climate, elevation or subsidence, the advent 

 of more vigorous forms, the ravages of disease etc., but while 

 all these forces may have played a part, there are some grounds 

 for thinking that the species itself may have a more or less de- 

 finite term of life and, as it were, carries its death warrant with 

 it. It is often assumed that variation in animals and plants 

 results in keeping each species fairly well adjusted to an en- 

 vironment that is not subject to sudden change, but recent ob- 

 servations on the ostrich incline the scientist to the idea that 

 in this species, at least, there is an inheifent tendency toward 

 degeneration, already manifested in the character of the 

 feathers, the loss of toes, and the lack of powers of flight. If 

 this degeneration should continue, say the scientists, the os- 

 trich is on the way out. Possibly many members of the an- 

 cient fauna and flora were similarly situated. Who knows that 

 a given species can last forever? Is it not possible that species 

 as a whole have a youth, maturity, old age and death similar 

 to that of the individual ? 



Edible Flowers. — Flowers and flower-buds are seldom 



