Dec. % 1901.] THE TROPICAL AGRICULTURIST. 
41^ 
the more telspabhic containing much quartz, but 
frequently such parts, instead of forming bands, 
occur as patches coarser than the rest. The felspar 
is greenish, which gives the rocks a rather dark 
appearance, and, by the aid of the quartz, a greasy 
lustre.. Occasionally we find large eye-shaped 
felspars about 1'5 inch in length. A typical 
specimen is a finely-banded rods;, the darker parts 
being composed of garnet, magnetite, and horn- 
blende. These bands vary in breadth from about 
•1 inch to mere lines. To these three consti- 
tuents the microscope adds a mineral, which I 
think is apatite. The magnetite is often embedded 
in the garnet ; its outlines are irregular or 
sinuous. An angle or a side of the garnet is 
often finished off by hornblende, and flakes of 
the latter frequently connect small outlying grains 
of the former. A few crystals of zircon are 
present. Quartz is abundant, and occurs in the 
usual elongated grains, whicli occasionally divide 
and ramify among the other constituents. The 
felspar is, for the most part, orthoclase with 
microperthitic inter-growth ; but a little plagio- 
clase is found. 
In some specimens the garnetiferous parts of 
the rock are represented by a short band, about 
•4 inch broad, composed almost entirely of garnet, 
while in other places the mineral is aggregated 
into patches, 
A specimen collected at the station before 
Bandarawella is essentially the same as the 
banded rock of the quarry above described. It is 
compact and greenish in colour, slightly banded, 
and with a greasy lustre. The irregular ouf.lines of 
the garnet and their association with green 
hornblende, magnetite, and the apatite-like 
mineral, merely repeat the characters of the 
Bandarawella rock. A very tew flakes of brown 
mica are found. The largest ?aruet is about O'lO 
inch in diameter. 
Similar rocks are met with by the new road 
which runs a''Ong the side of the hill above 
Bandarawella village. The numerous cuttings 
usually show the common sandy soil, which seems 
certainly to result from the disintegration in siiu/ 
ot the gneiss. The bands which characterized that 
rock are still clearly visible, and even the remains 
of the garnets can be seen as reddish spots. A 
few siTiall quarries and roail-cattings show a 
little variation in the character of the rock. 
Sometimes no garnets at all appear, and the rock 
is uniform when seen from a distance. Fre- 
quently, however, closer inspection reveals the 
presence of a few dark bands (specific gravity = 
3'16). Such and one possessed green hornblende 
as its dominant constituent, while a pleochroic 
augite was common, and biotite not rare. The 
rest of the slide was composed of plagioclase, as 
usual quite translucent. 
A thm section cut from a banded rock near 
here showed that, as in all instances met with of 
banded rock in Ceylon, no line of demarcation 
could be drawn between the dark and light por- 
tions of the slide. The darker parts contain 
hornblende and pleochroic augite ; and more 
sparingly, magnetite, brown mica, and garnet in 
order of frequency. The greater part of the horn- 
blende is an alteration-product from the augite. 
The remainder of the specimen is a light greenish 
rock containing large quartz. crystals, but as a 
whole much liner in grain than those from the 
Station Quarry at Bandarawella. Some red 
garnets about '0.3 inch in diameter catch the eye, 
^atl alsQ a few flakes of mica, 
(b) Road FROM Nuwara Eliya to Hakgala 
— In the quarry at the end of the lake at JS'uvvara 
Bliya occnis a dark greenish I'ock, with greasy 
lustre and some variation in degree of coarseness. 
Felspar is ptesent in considerable quantity, and 
also conspicuous elongated grains of quartz. 
A specimen, less finely grained than usnal, has 
been sliced for examination. The ferromagnesian 
silicates (both biotite and horn-blende) are in- 
conspicuous. The two constituents which builr'. 
up tlie greater part of the rock are quartz and 
orthoclase with microperthitic structure. Some of 
the felspars measure '4: inch across. The quartz 
is occasionally micropegmatitic, and accessory 
minerals are plagioclase zircon, pyrites, and (?) 
apatite. 
Cropping out by the side of the road to Hakgala, 
close to the quarry just mentioned, is a garnet- 
bearing rock closely related to the above, but 
more finely grained and richer in the ferromag- 
nesian silicates (specific graviby=3'll). A little 
farther on, in a quarry on the left bank of the 
stream, the rock of the Nuwara Eliya quarry 
appears. The rock is traversed by coarser quartz- 
felspar veins, essentially the same as the coarse 
patches from the Nuwara Eliya quarry, and in 
these rather large flakes of mica are scattered. 
Occasionally the mica-flakes have a distinct orien- 
tation, 
A small exposure above and to the right of the 
roid consists of a banded garnetiferous gneiss, 
containing some quantity of pink lelspar and a 
good deal of quartz. A vein or band of pink 
felspar and quartz, recalling the pinker parts of 
the gneiss (fi om which indeed it cannot be separa- 
ted), traverses the rock roughly parallel to its 
foliation. It measures about tUree inches across, 
and contains patches of mica. No hard-and-fast; 
line as of a contact can be drawn between the two. 
About 230 pace? down the road we find the 
compact greenish rock of the Nuwara Eliya quarry 
(specific giavity ="2'68). Its sections prove that 
this type is identical with the (iinki-<h banded 
gneiss, in spite of the rather striking difl'erence of 
colour : hence there can be, I think, no doubt that 
they form one group. 
A well-banded rock crops out about ^ mile 
below the entrance to Hakgala Gardens. The 
more felspalhic part is compact greenish-yellow, 
of uniform te.xture, of specific gravity 2 '59, 
and contains a pyroxene and a few inconspicuous 
red garnets. Tiie pyroxene . is monoclinic and 
pleochroic, but the pink colour which distinguishes 
this mineral elsewhere is almost imperceptible. 
The rest of the section consists of an aggregate of 
quartz orthoclase (microperthite and microcline 
absent) and plagioclase (extinction 7"), and a few 
grains of zircon. 
(c) Ohiya. — The recks of the railway cutting 
between Ohiya and the ascent to Horton Plains 
are identical with those of Nuwara Eliya and the 
road to Hakgala, so that a|aetailed descriptionh is 
unnecessary. 
Taken as a group, these rocks are distinguished, 
with a few exceptions, by a greenish 
colour accompanied by a greasy lustre, and 
usually by the presence of garnets. These 
garnets are associated with hornblende, 
a pleochroic pyroxene, magnetite, and 
frequently biotite. Irregular grains of quartz are 
common. There can be, I think, no doubt that 
these rock? are closely related to those of § IL 
p, m * 
