ECOLOGY. 307 



peatedly within an hour to visit the same flowers. Removing or covering 

 the ray-florets produced Uttle effect, but with a single exception all the bees 

 were deceived when the disk was covered with a circle of green leaf or paper. 

 The value of changes of color during anthesis in guiding bees to the 

 flowers with abundant nectar is supported by studies of Lotus and Lupinus. 

 One marked individual of Bombus californicus paid 134 visits to the fresh 

 yellow flowers of Lotus glaber, 4 to those turning pale orange, and none to 

 the old flowers which become orange-red. Another individual went to 250 

 fresh blue-purple flowers of Lupinus affinis, without once heeding the older 

 ones which were changing in color. 



Translocation and Storage in Autumn, hy F. E. Clements, Frances Long, and 



J. V. G. Loftfield. 

 In connection with the investigation of the life-history of the vegetative 

 plant, as well as that of the flower, studies have been made on photosynthesis, 

 translocation, and storage in a number of perennial herbs blossoming through 

 September, while several vernal and estival species were employed as checks. 

 Attention was directed chiefly to the activity of the stomata, the presence of 

 starch-grains in the guard-cells and mesophyll, and storage in stem, roots, and 

 rhizome, with especial reference to the shoots of the season and the buds for 

 the following year. Examinations were made at successive intervals after 

 the stomata were first found not to be opening in mid-day, while blooming 

 continued normally, and these were timed to take into account the effect 

 of minimum night temperatures, snow, and returning sunshine and warmth. 

 The effect of shade was also included. Practically all the species taken in 

 full sunhght on the second day after a snow that persisted for two days showed 

 no starch in the guard-cells or in the mesophyll. After a week of daily 

 sunshine, all of these again gave starch in the guard-cells and most of them in 

 the mesophyll also. Under unfavorable conditions, such as snow or cold 

 nights, the sun forms of Smilacina stellata and Geranium ccespitosum contained 

 no starch in the leaves, while the protected shade ecads continued to show 

 it in both guard-cells and mesophyll. As would be expected, the behavior 

 of the stomata was in agreement with that of the chloroplasts, complete 

 closure persisting during periods of snow or cold nights, and mid-day opening 

 being slowly resumed in some measure after successive days of sunshine. 

 The species differed much as to storage in stem, rhizome, and roots, the vernal 

 ones usually exhibiting the most. 



Factors involved in Opening and Closing of Flowers, by G. W. Goldsmith. 



Further work with Mentzelia nuda, which regularly opens in the late 

 afternoon and closes during the early night, as does Mentzelia multiflora, indi- 

 cates that the opening of the flowers is nearly independent of temperatures 

 ranging from 18° to 30°, but that the younger flowers may be caused to open 

 by a sudden and considerable decrease in the amount of light reaching the 

 plant. The work is being continued in order to determine whether the light 

 is effective through the thermal effect on the tissue, and hence the turgor, or 

 whether some other causal mechanism is involved. As in the case of Ment- 

 zelia multiflora previously reported, cutting the branch results in a loss of 

 floral movement for 24 hours or more, the flowers remaining in the condition 

 in which they were when removed from the plant. A life-history study of the 



