16 ON THE TERTIARY FLORA OF THE ARCTIC REGION. 
bearing spathes, experiments may be tried artificially when an ocea- 
sion again offers whether any explosive sound results on their being 
opened, although, from what I have observed formerly, the result would 
not be decisive from a few solitary examples.” — George Bennett. 
` < Remarks on the Bursting of the Spathe of Palms, and Opening of 
Leguminous Fruits, by Mr. J. Sadler, and read before the Botanical 
` Society of Edinburgh (Dec. 11, 1862), complete all the evidence that 
at present can be offered. 
Mr. Sadler gave the views of different authors regarding the burst- 
ing of the spathe of Palms with an explosive report. That some spe- 
cies of Palms in their native habitats may make, while bursting their 
spathes, a sound, caused by compressed air, audible to a very attentive 
ear, he did not deny; but he was of opinion, from certain experi- 
ments which he and others had made on Ptychosperma Cunningham, 
that in this country no indication of a report (as affirmed by some) 
was met with. The author then explained that the crackling sound 
of various leguminous fruits while shedding their seeds was not (as 
supposed) due to heated or compressed air, but to the shrinking or 
tension of the tissues. He concluded by reading extracts from a letter 
which he had received from Mr. W. Bell, of Saharunpore Botanic Gar- n 
den, in which he stated that, from all the information he had gathered 
at Ceylon, Caleutta, and elsewhere, he could find nothing to support 
the theory of explosion caused by heat developed within the spathe. 
ON THE TERTIARY FLORA OF THE ARCTIC REGION. 
By Proressor H. R. Gerrert, or BRESLAU. 
(Translated from the Bulletin of the Russian Academy, iii. 448.) 
It is more than probable that at the commencement of every geolo- 
gical epoch a change of climate took place, and that even in the Tertiary : 
period our own regions enjoyed a higher mean temperature than they 
do at present. Whether this was the case in the higher latitudes was » 
formerly but little discussed, although the existence of considerably . 
large trunks of bituminous woods in countries like Iceland, Greenl 
and Northern Siberia, where at present only shrubby vegetation is me 
