706 
No. 188. Homestead Eawge, Northeex Eailwat (QrEENSiAND). 
W. H. Bands’ Collection. Sp. Gr. 2-58. 
Colour, red. Would lie placed by Professor Hutton in tbe same class as Nos. 
255 and 257. 
Orthoelase is tbe prevailing felspar. Sometimes tbe latter is quite clear and 
limpid. Tbe kaolinized felspars are stained rod with oxide of iron, and sometimes 
ferrite is concentrated round centres, tbe eyes of nbicb are opaque, tbe edges being 
transparent and just stained. 
(Sec/foM.— Micropegmatito occurs, sbowing tbe simultaneous extinction of tbe 
interpenetrating quartz wbcn tbe section is revolved. Tbe quartzes contain tbe usual 
fixed and oscillating bubbles. Tbe inicromotcr-serew reveals planes formed of extremely 
minute inclusions vvbiob bavo a faintly pink tinge to my eye, and are transparent. The 
inclusions are probably glassy. Sometimes their shape is .similar to that of tbeinclusions 
described as occurring in quai’tzesdn tbe Cooktown granite, but more often they are 
round or ovate; the smallest would measure less than '0001 inch. The micrometer- 
screw shows bow tbev traverse the crystal in various planes, whoso directions are 
independent of any of the crystal axes. Tbe quartz, when porphyritic, is often idio- 
morpbic, as is also the orthoelase. Macroscopically, the rock carries sparse black specks, 
which have not been determined. 
No. 202. North oe Chijvamak’s Gully, Cape Kiver Gold Field (Queensland). 
W. H. Bands’ Collection. Sp. Gr. 2'G63. 
Colour, nearly white. Quartz, white mica, felspars, and garnets, the latter pale 
yellow. The structure is granular, granitic, or holocrystalline, and the minerals are all 
fresh and transparent. 
Section . — The felspars are most abundant, and therefore come first. One felspar 
is much kaolinized, but still sutficiently fresh to identify. 
The axes of extinction, on either side of wcdl marked cleavages, are — right, 
7° 20' ; left, 8° 50'. 'The cleavage being so well marked, and the angles of extinction 
with regard to it being also well marked, show that the section is probably cut parallel 
to the plane of symmetry 010, and the cleav.nges must be parallel to the basal piuakoid, 
all pointing to orthoelase which is rather fresh. In addition, there are plagioclase 
felspars, some very finely striped and others eoarsely striped, suggestive of oligoclase. 
The mica is a potash mica, and possibly muscovite. 'The sections show marked 
absorption for rays vibrating parallel to the basal planes in such crystals as are cut 
transverse to the lamell®. 
The garnets appear brilliant and rough, of course, by reflected light, owing to 
their high index of refraction. 'Their optical properties are normal, and irregular cracks 
traverse the crystal. 'The gr.ains average '01 inch in diameter, and are of a pale-yellow 
pink colour. Probably they are almandiue garnets. The inclusions in the quartzes 
are very small, being only just discernible under the f-inch objective, and under the 
i-iiich a few minute moving bubbles wore to bo seen. 
Nos. 240, 241, 242, 243. Victoria Beef, Charters Towers (Queensland). 
These rocks were collected by the lion. H. Mosman, M.L.G., with the view of 
determining, through ProFe.ssor Judd, whether there is any difference between granite 
bordering gold-bearing reefs and grani'.e bonlering non gold-bearing reefs. The four 
samples were sectioned in my laboratory ; and before their despatch to Professor Judd, 
