THE AMERICAN BOTANIST. 87 



Biennials. — The carrot is a biennial — so the books say — 

 but it is not uncommon to find in a field of carrots, specimens 

 that fruit the summer the seeds were planted. The whole 

 philosophy underlying the development of biennials is that cer- 

 tain plants must first secure a store of food before they can 

 form their flowers and seeds. It takes the radish only a few 

 weeks to accomplish this, but carrots, parsnips, salsify and the 

 like require a longer period. When the season happens to be 

 favorable and enough food is secured there is no reason why 

 these plants should not follow the example of the radish. The 

 conception of a biennial therefore, is not as definite as that of 

 the annual or perennial. Biennials are more likely to be influ- 

 enced by weather and climate. In regions with a long growing 

 season, the line between annuals and biennials breaks down 

 more or less completely. 



Storage Organ of the Live Oak. — A large number of 

 plants store their food in their roots and this is supposed to be 

 because it is safer there, being protected by the earth from too 

 great evaporation, many animals, and various other harmful 

 agencies. Storage of food in this way is usually carried on by 

 mature plants ; it is seldom that one finds a mere seedling so 

 worldly wise. Such cases occur, however. The seedlings of 

 the giant cactus apparently appreciating the fact that they are 

 to grow in a dry region store up a quantity of water in the 

 caulicle, and often in this way become attractive morsels to birds 

 and other animals on the lookout for juicy food. The seedling 

 of the live oak does not store up water and it has no need to 

 store food at once, since, like other oak seedlings it has been 

 provided with a good sized food store within the cotyledons, 

 but it does not seem satisfied to follow the custom of the others 

 and draw upon this foodstore as needed. Instead it sends out 

 upon germination, a much elongated common petiole which 

 enables the short root to penetrate the soil. Then the young 

 root enlarges, and the food stored* in the acorn is promptly car- 



