74 OPENING OF PALM SPATHES WITH AN AUDIBLE REPORT. 
length the moment arrives when the pressure against the axis is so : 
strong, and the attachment of the stalks to it so weak, that a hot gleam | i 
of the sun is sufficient to detach the scales with sudden violence. In 
considering these appearances at the time when they presented them- 
selves, it seemed to me that the process might aid in the dispersion of 
the seed. The leaves encompass the cone on every side, and form so 
dense a circuit, that the escape of the drupes appears impossible. The * 
explosive faculty of the mature cone may overcome this difficulty. I 3 
may add that, if you examine the axis of the female cone of an Ence- — 
phalartus, you will see that the scars, showing the attachment of the — 
scales, are smooth, because the vessels in the bundles of woody fibres 3 
have closed. According to the preceding explanation, the e d 
is analogous to the dispersion of seed in many other cases. On a : 
summer's day, walking beside a hedge of Ulex Huropeus or Me 
scoparium, I have listened with much interest to the crackling of the — 
ripe pods. A circumstance occurred here two or three years ago, which / 
may throw some light on the subject. Certain members of the family . 
were seated one summer's day at an open window looking into the t: 
garden, when they were startled by a noise. It appeared to have pro- — 
ceeded from the sudden expansion of the leaves of a large and fine Four- 1 
croya gigantea, which were, till then, closely wrapt round one another." 
—James Yates.* 
Another singular instance of detonation was communicated (‘Bon- : 
plandia,’ vol. x. p. 85) by Mr. Smith, of the Royal Botanic Gardens, - 
Kew :—“ More than thirty years ago I and my family were roused | 
from a sound sleep by what we took to be a discharged pistol, and -— 
proceeding from the lower part of the house. The thought of being - 
surprised by housebreakers was so uppermost in my mind, that Iin- - 
stantly struck a light, and, arming myself with the only weapon abo 
hand, a poker, descended downstairs. Fully expecting to encounter & 
strong smell of gunpowder and a gang of thieves, I opened the door — 
of the room whence the sound had come. To my surprise, I found . 
neither the one nor the other, the room being undisturbed, and nothing ; 
to be seen. But, on advancing, my bare feet trod upon several sharp - 
things, which, on closer inspection, turned out to be the cocca of Hura : 
crepitans, the Sandbox-tree. The mystery was solved. We had 4 
* Also published in ‘ Bonplandia,’ vol. x. p. 86. 
