146 



THE AMERICAN BOTANIST 



bedded in the moss on the trunks and branches of a species of 

 yellow wood {Podocarpus) . 



Flowering Plant Forms. — The true flowering plants 

 divide naturally into the two groups of Monocotyledons and 

 Dicotyledons, the separation depending upon whether they have 

 one or two seed leaves. The dicots comprise by far the larger 

 group, a conservative estimate placing their number at nearly 

 110,000 species while the monocots number less than 25,000. 

 In the dicots there are approximately 46,000 species with 

 sympetalous flowers, that is, with parts united, and 62,000 with 

 polypetalous and apetalous flowers. In this latter group, 50,000, 

 or nearly five-sixths, have superior ovaries. In the sympeta- 

 lous flowers, 22,000, or about half, have superior ovaries. 

 Approximately 12,000 plants in the monocots have superior 

 ovaries. A curious thing connected with this subject is the 

 fact that there are practically no monocots with sympetalous 

 flowers. The few instances that occur, such as Convallariay 

 Asparagus and Alctris serve as the exceptions which prove 

 the rule. 



Tube-rose or Tuber-ose. — The common names of 

 plants are derived from many sources and are often older 

 than the scientific terms applied to them, — especially if they 

 happen to have beautiful flowers or a reputation for curing 

 disease. In many cases the scientific' names are adaptations 

 of the older common names given intentionally by educated 

 people, but in the common name given to that cinnamon- 

 scented bulbous plant commonly called the tuberose we have 

 an example of how ignorance may also contribute to the 

 nomenclature of plants. Our plant, which in scientific par- 

 lance is Polianthes tuberosa has nothing in connection with 

 roses. The popular name is a corruption of the specific name, 

 tuberosa, which means ''producing or resembling tubers." 

 Polianthes tuberosa was apparently too- lengthly for popular 

 usage and the first half was accordingly dropped, the plant 



