Geological magazine . than biotite. A further structural peculiarity is theoccasional presence of myrmekitic intergrowths of quartz and biotite(Fig. 2) and quartz and hornblende. ^ J. P. Holmquist, Studien iiber die Granite von Schweden : Bull. Upsala, vol. vii, p. 116, 1904-5. J. A. Thomson—Rocks of Western Australia. 217 Orthite occurs in the centres of fairly large prisms of epidote, andhas determined pleochroic haloes in the biotite. Zircon and apatiteare abundant in minute prisms. Of these rocks, the one is wellfoliated, the other massive, and mineralogically they differ chiefl
Geological magazine . than biotite. A further structural peculiarity is theoccasional presence of myrmekitic intergrowths of quartz and biotite(Fig. 2) and quartz and hornblende. ^ J. P. Holmquist, Studien iiber die Granite von Schweden : Bull. Upsala, vol. vii, p. 116, 1904-5. J. A. Thomson—Rocks of Western Australia. 217 Orthite occurs in the centres of fairly large prisms of epidote, andhas determined pleochroic haloes in the biotite. Zircon and apatiteare abundant in minute prisms. Of these rocks, the one is wellfoliated, the other massive, and mineralogically they differ chiefly inthe larger amount of hornblende compared to biotite in the massive rock might easily be taken in the hand-specimen for anordinary granite, but from its structural peculiarities must be assignedto the gneiss complex, which at Albany is intruded by a coarselyporphyritic pink granite of probably much later age. Among thegneisses garnetiferous varieties were seen, but have not been studiedin thin E^ ^ Zircon. Fig. 2. Detail from gneiss showing biotite myrmekitically intergrown withquartz in the bottom left-hand corner and associated with and partially-enclosing orthite, apatite, magnetite, and zircon. Magnification, 34 diam. The writers thanks are due to Messrs. A. Gibb Maitland, Harry , and C. G. Gibson for unfailing kindness during hisresidence in Western Australia, and for much verbal informationwhich has enabled him to form clear views on the geology of districtswhich he has not been able to visit. To Dr. J, M. Maclaren, also,he is indebted in a manner difficult to estimate, since most of theabove ideas were freely discussed with him during a years closeassociation. None of these gentlemen, however, can be committed tothe classification outlined above. 218 Rev. 0. Fisher—Works of Prehidoric Man. V.—Some Handiworks of Early Men of various ages. By the Eev. 0. Fisher, , (WITH FOUE TEXT-FIGUKES.) IN the follow
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