7^ THE PLANT WORLD. 



Back on the mesa among the rocks are many Eriogonums. One 

 species, with its grayish stems and leaves, rose-colored flowers and 

 diffuse habit, and another, dressed in dark green and yellow, seem too 

 dainty for their environment. 



The Compositae we have always with lis, and this region is no ex- 

 ception. Gutierrezia, Aplopappus, Bigelovia, Aster, Erigeron, Zinnia. 

 Artemisia, Senecio and many other genera are represented. Here and 

 there is a patch of grass, enough to be called "fine feed" by a cow- 

 boy, although one cannot but wonder how stock manages to exist with 

 such scanty supply. Species of Sporobolus and Panicum are found, 

 but the commonest grasses are of the genera Epicampes, called saca- 

 ton, and Bouteloua, of which there are several species. 



NOTES UPON THE GROWTH OF STEMS AFTER 



BEING CUT. 



By Byron D. Halstead. 



THE very evident elongation of the stems of Scarlet clover [Tri- 

 foliuin mcarnatuni) after having been cut and placed in a vase 

 led me to make a series of measurements of the elongation 

 with this species and that of some other long, rapidly growing 

 flower stalks. 



The test was made by cutting and at once placing the cut ends in 

 water, after which the stems were marked off into half inch spaces by 

 using India ink applied in narrow lines with a camel's hair brush, and 

 the stems returned to the vase of water. The following are some of 

 the results with the Scarlet clover: 



No. I. Twenty-six half-inch spaces were marked off, or a total of 

 thirteen inches, on Saturday morning. May 15th. At the end of five 

 hours the marked thirteen inches had elongated to thirteen and a half 

 inches. A week later the marked portion of the stem had elongated 

 to seventeen inches, or a total increase of four inches! 



This increase was confined to the upper six spaces or three inches, 

 and embraced the upper internode and upper half of the one below it 

 as follows: the first internode below the head from y^ inch to 2^ 

 inches; the second internode from Y^ to i3/^ inch; the third (just 

 above the node) from >^ to yi inch ; the fourth internode from >^ to 

 24 inch; the fifth internode from >^ to i^ inch, and the sixth inter- 

 node from }4 to }{ inch. 



Another upper ten inches of a Crimson clover stem elongated to 

 fourteen inches, or an increase of four inches, as in the last case. The 

 increase was confined to the upper 5 inches as follows: — 



