80 THE AMERICAN BOTANIST. 



sure the insect does not guard the yucca for mere pleasure for 

 before she places the pollen on the stigma she prudently lays 

 one or more eggs in the ovary where the larvae can feed upon 

 the developing seeds, but how did she know that pollination 

 was necessary to seed formation — many a grown up human be- 

 ing does not know that ! And even knowing this, how did she 

 discover how to go about the work of pollination? Among 

 the "lords of creation" only a few specialists are familiar with 

 the process. Probably this is the only insect in the world that 

 intentionally cross pollinates flowers. Nature has been kind 

 to the moth also in the matter of dress. She is colored exactly 

 like the stamens and when resting head down in the flower — ■ 

 her favorite position during the day — can hardly be distin- 

 guished from those organs. Just before dusk she begins her 

 self-appointed task and any body who has access to a clump 

 of blooming yuccas may see her at work if they will. Her 

 progeny, fond as they are of young yucca seeds, always leave 

 some to ripen and thus keep up the supply of yucca plants. 



Orientation of Radishes. — A short time ago. Horti- 

 culture published a story to the effect that a Jap has discovered 

 that the radish and other root crops always put out their lateral 

 roots in an east and west direction, in consequence of which 

 we were advised to always plant such crops in rows running 

 north and south so that the lateral roots might push out into 

 the soil between the rows and thus get more food. A little 

 observation however has shown that the Jap was only partly 

 right. The basis for his statements is simply this : the radish 

 produces its lateral roots in two lines lengthwise of the main 

 root. Sometimes these push out east and west and sometimes 

 north and south. It seems to be merely incidental which way 

 the roots should project; otherwise we should have to give the 

 plant credit for ability to discern the points of the compass, — a 

 thing no plant can do. Even the compass plant turns its leaves 

 under the stimulus of heat or light, never magnetism. Other 



