Reviews—Geology of Federated Malay States. 565 
but no well-characterised trachytes or basalts are present, though 
olivine occurs in some of the Tertiary andesites. Many of the 
andesites have a groundmass which appears to be pilotaxitic, but 
Professor Sollas has found that there is always in these rocks 
a matrix of quartz; the structure is really micropoikilitic. His 
observations on the isotropic material which replaces the felspar 
phenocrysts in certain modes of decomposition are very interesting. 
They had previously been described as fused or vitrified felspars. 
Many of the rocks are filled with secondary quartz or opal, sericite, 
and chlorite; in others there is much tridymite. Some of the 
andesites show fluxion brecciation ; that which has been described as 
Wilsonite is probably of this nature, and in another case we have 
a hornblende hypersthene andesite in which the phenocrysts have 
been broken up and seem mylonised before the matrix had completely 
solidified. Another very interesting group of rocks is the spherulitic 
rhyolites of this region; some of them are well known to contain 
large spherulites with branching or ‘cervicorn’ processes, and excellent 
figures of these wonderful structures are given in these two volumes. 
III.—Grotocy or tHE Frperarep Matay Srares. 
Gxotoeist’s Report or Proeress. September, 1903-—January, 1907. 
With rough sketch-map (topographical). By J. B. Scrrvenor, 
Geologist F.M.S., formerly of H.M. Geological Survey of Great 
Britain. 8vo; pp. vi, 44. Printed at the F.M.S. Government 
Press, Kuala Lumpur. 1907. Price one dollar. 
({\HE Government of the Federated Malay States are to be con- 
gratulated on having requisitioned the services of so capable 
and energetic an officer as Mr. J. B. Scrivenor to unravel the many 
intricate problems connected with the geological structure of that 
country. The geologist’s work in these regions has been carried out 
under great difficulties, both on account of the want of good, service- 
able topographical maps and because of the dense jungle which covers 
the country at high altitudes; nevertheless, the author gives us an 
excellent account of his three years’ explorations. Some of the items 
of information have already appeared in ‘‘ The Progress Report”’ for 
1904, a notice of which has been published in the GeroxocicaL 
Maeazine for 1906, pp. 40, 41, in association with another of the 
author’s reports, ‘‘ On the Geology of the Residency of Sarawak,” etc. 
, The present Report is divided into two sections, viz. ‘Structural’ 
and ‘ Economical.’ Under the former is described ‘the Chert Series,’ 
‘the Raub Series,’ and ‘the Tembeling Series.’ The first of these, 
occurring at Tras, Raub, Lubok Plang, etc., contains Radiolaria, and 
may be analogous to the Culm of Devonshire or Sumatra; the next 
has yielded Carboniferous Cephalopods at Mill Gully and Goa, which 
have been determined by Mr. G. C. Crick, and remnants of a Permian 
fauna at Lubok Sukum, which favours correlation with the Upper 
Productus-limestone of the Salt Range, India; whilst the Tembeling 
Series is made to include a number of Triassic shells from Kuala 
Lipis, described some years since by Mr. R. Bullen Newton,’ and 
1 See Grou. Mac., 1901,"pp. 128, 189. 
