FOREIGN JOURNALS IN BOTANY. 
341 
in them by the process of growth and development. They have arrived at the 
following conclusions:—1. The presence of gases in the interior of the root of 
the stem, and of the branches in the Mulberry and Vine, is a normal and con- 
stant fact. 2. The composition of these gases changes with the epochs of vege¬ 
tation. 3. During the period of inactivity, carbonic acid is in very small pro¬ 
portion, and is scarcely appreciable. Oxygen is present to the same extent as 
in atmospheric air. During the phase of activity the contrary takes place, and 
the changes are more marked in proportion as the vegetation is more energetic; 
with the progress of vegetation, the proportion of oxygen diminishes. 4. In 
the roots, during the epoch of vegetation, the quantity of oxygen is not so great, 
while that of carbonic acid is-greater than in the branches examined under the 
same circumstances. 5. In the branches, as in the roots, there is an inverse 
relation between the oxygen and the carbonic acid; by adding to the normal 
oxygen that disengaged under the form of carbonic acid, we obtain a number 
which is scarcely above the proportion of cxj^gen in the air. 6. In the Mul¬ 
berry and the Vine, injections do not penetrate the pith or the bark, whether 
in the branches or roots. The ligneous layers are alone permeable to mercury. 
The more the formation of vessels increases, the easier and more complete are 
the injections. The injections are fuller in the roots than in the branches; 
they are also more in the branches than in the young herbaceous shoots. In 
the old stems of the Mulberry, the central layers cease to be permeable. 7. 
Microscopic examination proves that the injection specially penetrates the pitted 
and reticulated vessels, and also the spiral vessels in the young herbaceous shoots. 
8. The pitted vessels show distinctly the mercury in the areolm, as if in so many 
little pouches formed by thin portions of the wall; the same observations have 
been made in regard to the reticulated vessels. 9. The contents of the vessels 
expelled by the mercury are variable. Sometimes gas only is sent out: this is 
the case in winter and after dry weather. Sometimes the gas is mixed with sap, 
which is more or less abundant according to the epoch of vegetation and ex¬ 
ternal temperature. These two latter conditions regulate, in a certain degree, 
the contents of the vessels. 10. The contents are so variable that in plants the 
root-vessels of which contain gases and sap, the stem-vessels contain only gases, 
or inversely. 11. The presence in the vessels of animals of oxygen and car¬ 
bonic acid mixed with the blood, constitutes one of the best established facts in 
animal physiology; the presence of the same gases mixed with the sap in the 
vessels of plants, and the modifications which they there undergo, seem to esta¬ 
blish an interesting correspondence between these two kingdoms.— Botanical 
Society of Edinburgh. 
Sleight of Australian Trees. 
The marvellous height of some of the Australian, and especially Victorian 
trees, has become the subject of closer investigation, since of late, particularly 
through the miners’ tracks, easier access has been gained to the back gullies of 
our mountain-system. Some astounding data , supported by actual measure¬ 
ments, are now on record. The highest tree previously known was a Karri- 
Eucalyptus (Eucalyptus colossea ), measured by Mr. Pemberton Walcott, in one 
of the delightful glens of the Warren River of Western Australia, where it 
rises to approximately 400 feet high. Into the hollow trunk of this Karri three 
riders, with an additional packhorse, could enter and turn in it without dis¬ 
mounting. On the desire of the writer of these pages, Mr. D. Royle measured 
a fallen tree of Eucalyptus amygdalina , in the deep recesses of Dandenong, and 
obtained for it the length of 420 feet, with proportions of width, indicated in a 
design of a monumental structure placed in the Exhibition ; while Mr. G. Klein 
took the measurement of a Eucalyptus on the Black Spur, ten miles distant from 
Healesville, 480 feet high ! Mr. E. B. lleyne obtained at Dandenong as inea- 
