On the Irritability of the Fronds of Asplenium bulbiferum, With Special Reference to Graviperception . ue to theproximity of the soil. When the pot was placed upright, bhe frond attainedthe vertical position. Again placed horizontally, the frond rose to an angularheight of 70° and then dropped. This was not due to the cause justexplained, since the same thing has occurred in experiments when the potwas upright (see below). The frond is seen to oscillate for some time, andfinally to take up a position at an angle of 45°, the recorded deviations fromthis being well within the limits of experimen
On the Irritability of the Fronds of Asplenium bulbiferum, With Special Reference to Graviperception . ue to theproximity of the soil. When the pot was placed upright, bhe frond attainedthe vertical position. Again placed horizontally, the frond rose to an angularheight of 70° and then dropped. This was not due to the cause justexplained, since the same thing has occurred in experiments when the potwas upright (see below). The frond is seen to oscillate for some time, andfinally to take up a position at an angle of 45°, the recorded deviations fromthis being well within the limits of experimental error. Text-fig. 6 is from a tracing made on glass of the actual position occupiedby a fern frond on the recorded dates. A complete movement through 90°having been obtained by previously placing the pot horizontally, it was on Fronds o/Asplenium bulbiferum. 149 February 12 replaced in the upright position, making the frond thereforehorizontal. It was slowly rising, till on the 18th it had reached an angularheight of 45°. Eound that position it oscillated, gradually uncurling, till -. CO CD. Fig. 6. this was complete on March 2. Soon after, the sagging effect due to theweight of the developing leaflets becomes apparent in the upper part of thefrond. It will be seen that epinasty is not well marked in this particularcase. As I read it, this record illustrates most of the movements describedabove, except that due to light, which was shown in the diaheliotropism ofthe leaflets not represented. 3. The Statolith Apparatus of Asplenium bulbiferum. Most attention has been paid to the frond, though some stems have beenexamined. Starch does not seem to be very abundant in the rhizome of thisplant, but was always found at the apex. In one case, in a stem whichseemed dormant, very little was present, and it was quite are, however, always present beneath the rudiments of adeveloping frond, though some diversity is shown in the cytology of thestatocyte. In one c
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