SCIENTIFIC SUMMARY. 
91 
tureless ganoine. Adjacent trees of this kind also freely communicate with 
each other hv means of arched branches, passing around and between the 
vertical canals between which their stems are situated. A beautiful kos- 
mine-like layer is thus formed below the ganoine ; it must be noted, how- 
ever, that small lacunae are occasionally seen among its minute tubules. In 
the true bone below, lacunae of the ordinary type abound in the meshes of 
its Haversian network.” 
The Characters of the Irish Chalk. — A very good paper on this subject has 
been presented to the Irish Geological Society by Mr. E. T. Hardman, 
F.B.G.S.I. We shall give the result of chemical examination first. The fol- 
lowing is the summary of the analysis. The specimens used were obtained 
from an old quarry in the townland of Leg-mum, about a mile and a half 
north-east of Stewartstown. The chalk. is so indurated as to be in reality a 
hard splintery limestone. 
CaC0 3 
M 9 C0 3 
Si0 2 . 
A1 2 0 3 
*V> 3 
FeO . 
97-320 
0-890 
0-537 
0-273 
0-095 
a trace. 
ZnO 
BaO 
SrO 
k 2 o , 
Na,0 > 
, (Mery perceptible even in small 
r ‘ ces - 1 quantities of the chalk. 
a trace, 
a trace. 
amount not estimated. 
The author accounts for its hardness, in which respect it differs much 
from English chalk, by assuming an enormous pressure of the Irish basalt 
which was poured out over it. He says, when it is remembered that in the 
Hebrides the basalt reaches a thickness of between 3,000 and 4,000 feet, and 
that the Irish basalt, although now but from 500 to 1,200 feet thick, may 
have had similar proportions, there is no difficulty in referring the con- 
solidation of the Irish chalk to pressure alone ; for, taking the original 
thickness of the basalt at only 3,000 feet, the pressure on each square yard 
of underlying chalk would be about 2,000 tons. The analysis, which is 
extremely similar to one by Mr. Wonfor of the Chalk of Cushendall, 
Co. Antrim, shows that it is a limestone of very great purity, the per- 
centage of silicious matter being so small as to be quite insignificant. It 
should, therefore, be of the highest value in many chemical manufactures, 
especially that of bleaching-powder. But it is remarkable that although in 
the North of Ireland an immense quantity of this material is used up, it is 
not made there, but is mostly imported from Glasgow and Lancashire. So 
far as he knows, there is not a single Chloride of Lime Works in Ulster. 
British Fossil Botany in 1872. — The best resume we have seen on this 
subject is that published by Mr. W. Carruthers, F.R.S., in the “ Geological 
Magazine,” October 1873. It is a most valuable list, and the author has 
added to the interest which such a list would have by briefly adverting to 
the nature of each paper. We trust that Mr. Carruthers will continue this 
record, which we should much like to see extended to other portions of 
palseontography and geology. 
European Mammalia at the close of the Miocene Period. — Under the title 
of the “Fossil Animals of Mont Leberon,” M. A. Gaudry has just pub- 
lished in Paris a paper which is of some interest, and which is very fully 
dealt with in a review in the 11 Geological Magazine,” October. His con- 
clusions are based upon the discovery of numerous intermediate forms 
