70 OPENING OF PALM SPATHES WITH AN AUDIBLE REPORT. 
in the * Gardeners’ Chronicle’ from the pen of Dr. Seemann, describing 
the bursting of a spathe of Ptychosperma Cunninghami with an audible re- 
port ‘ almost loud enough to have proceeded from a pistol,’ inthe Palm- 
house at Kew—the explosion being attributed to ‘a great accumulation 
of heat, developed by the anthers whilst inside the spathe.’ The au- 
thors then stated that they had had ample opportunities for observing 
the flowers of the Ptychosperma in all their different stages of develop- 
ment in the Palm-house at the Edinburgh Botanic Garden, and as yet 
had never seen anything which gave the least indication of a sudden rup- 
turing of the spathe. In some cases they had seen the old foot-stalk — 
of the leaf which covered the spathe fall off two or three days before A 
the spathe showed any signs of bursting, and when it did burst it — 
opened gradually from the base to the apex, generally on the dorsal as- 
pect; indeed, they had only observed a single instance where the rup- 
ture occurred on the ventral side. Again, they had seen the spathe 
burst two or three days before the old foot-stalk fell off, and when it — 
fell upon the floor it generally gave a pretty sharp crack, which they 
thought had been probably regarded as proceeding from the bursting of 
the spathe, as Dr. Seemann states that the spathe in bursting ‘ forced 
oif the remnant of the old leaf-stalk When the spathe bursts previous 
to the fall of the foot-stalk that covers it, as soon as it is removed the 
branches of the spadix immediately expand, and, to all appearance, it 
looks exactly as if the spathe, in the act of bursting, had knocked off 
the foot-stalk. Dr. Seemann supposes that the report was due toan — 
accumulation of heat, produced by the anthers. This, however, the - i 
authors thought could not be the case, as a considerable time elap : 
between the bursting of the spathe and the opening of the flowers; this — 
they had never observed to be less than three weeks, and generally more —— 
than a month. A tree in the Palm-house at the Botanic Garden burst - E 
its spathe five weeks ago, and had not yet a single flower expanded. — | 
After the bursting of the spathe, the branches of the spadix continue to 
increase both in length and thickness, and until they have reached their 
maximum development they had never seen a single flower expand. — 
Dr. Lindley, in his * Introduction to Botany,’ and Dr. Balfour, in his —— 
* Class Book," both state that the greatest amount of heat during the — 
period of flowering is when the anthers are ready to discharge their — 
pollen, after which it gradually declines. At the time the spathe bursts _ 
the flowers are in a very imperfect state, the stamens being very imma- — 
Ea) = Ge te SW I MO VENE RES EE 
