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Page:Popular Science Monthly Volume 37.djvu/388

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374
THE POPULAR SCIENCE MONTHLY.

Allen and Maverick Counties, Kentucky, and Chattooga County, Georgia, appeared to be identical with the one from Santa Rosa, though found at places so distant from each other and described as independent falls, while none showed the striking fracture of the Butcher specimens.

As the irons examined were among the most compact and malleable of any in our collections, the result suggests a new way of identifying fragments of the same original mass, where external features are not sufficiently decisive, and, moreover, shows the care that must be taken in determining supposed new falls.

 

OBSERVATIONS UPON DOUBLING OF FLOWERS.
By BYRON D. HALSTED, Sc. D.,

PROFESSOR OF BOTANY IN RUTGERS COLLEGE.

FUNCTIONALLY a flower is for the production of offspring, and in structure it may be considered as a transformed stem with its metamorphosed leaves. In a typical flower—that is, one having all the parts present and in an easily recognized form—there are four sets of organs. The calyx forms the outer whorl of leafy organs, and next within is the corolla, usually bright-colored and showy. Inside of these two cycles of floral envelopes are the essential organs: first the stamens, which bear the male element as pollen-grains; and the pistil or pistils, occupying the center of the flower, the lower portion of which bears the seeds. In the production of seed we find the aim and end of all floral structures. The pistil remains after the flowering period is past and becomes the fruit, which may or may not be accompanied by other portions of the flower. The stamens serve their purpose as they shed their pollen, and usually quickly wither away, and the latter is generally true of the petals.

As above stated, all the several parts of a flower are now considered as modified leaves. The calyx is often green, leafy, and indistinguishable from ordinary foliage. All gradations may be found between calyx and corolla. The bright color is no argument against petals being leaves, for leaves of the common sort often assume the most brilliant colorations. Other wild plants illustrate the transition from petals to stamens—as, for example, the flowers of the water-lilies; and pistils are frequently broad, green, and leaf-like, especially after the seeds are ripe, and the two infolded halves open out and take on the form and function of foliage.

We do not need to extend our examination upon this point in search of proof for the morphological significance of the floral