212 BOTANICAL GAZETTE. 



24 or 48 hours, the stem increasing in diameter as well as in length; in 

 other cases it took longer. No finer example of rapidly dividing cells 

 can be obtained anywhere than is furnished by these elongating pedun- 

 cles. Then conies another resting period, after which the convolute pe- 

 tals begin to elongate, gaining nearly their full length while still rolled 

 together. Presently a loosening up is noticed near the middle of the 

 roll of petals, the edges beginning to free themselves from any overlap- 

 ping and thus giving elbow room for the next movement. As is very 

 well known the petals are strongly reflexed, just as in Dodecatheon, 

 and I was somewhat curious to see how the reliexing took place. Close- 

 ly as I Matched, several buds opened without my catching a glimpse of 

 the manner; but finally I was rewarded by seeing the retlexed position 

 gained in a variety of ways. The usual way seems to be for the two upper 

 petals to fly back suddenly like liberated springs, and the remaining 

 three to come back slowly one at a time, with an almost imperceptible 

 movement, always in the same order, the innermost petal being last. 

 Sometimes, however, all five spring back at once, spreading out like the 

 rays of a star, and then usually the two upper ones become at once com- 

 pletely reflexed, leaving the other three to assume the position gradually. 

 There seems thus to be a combination of a simple mechanical movement, 

 the sudden springing from a confined position, and a- vital movement 

 which brings the released petals slowly back to the required position. 

 Mr. Darwin 1 has spoken of the movement of the peduncles in bending 

 downward and burying the pods and this movement was beautifully 

 shown in the specimens examined, and the circumnutation was also 

 very noticeable. Circumnutation in the slow movement 

 of the reliexing petals is very evident, as they describe quitt a sensible 

 arc before settling into their permanent positions and even then continue 

 it and become quite twisted. This might partly be due to their having 

 been in the convolute arrangement in the laid, but this cannot entirely 

 account for it, and may not this very convolute arrangement look to 

 circumnutation at least as an abettor, and the tension which causes the 

 upper petals to spring back when released be stored up by its restraint? 

 So then this same Cyclamen Persicum, which yielded to Darwin illus- 

 trations of movement in cotyledon, peduncle, and leaf, continues the 

 story in the petals. 



It might be interesting in this connection, to note the presence of 

 cleistogamous flowers. In some the peduncles never elongated, but 

 in one it grew as rankly as those of other flowers, and one 

 stunted petal crept out of the calyx-tube, but that was all. The stamens 

 though were full to bursting of pollen, which does not look like cleis- 

 togamy, and the pod was the best formed of all and full of seed. It 

 would seem as if all the cleistogamous flowers should have elongated 

 ped uncles if the habit of burying the pods is to be preserved.— J. M. C. 



'Power of movement in Plants, p. 433. 



