Carboniferous Fossils from Siam. 113 



Walker collection at Cambridge, with notes on certain of these, 

 and for the loan of specimens ; to Mr. T. H. Withers for his report 

 on the Upper Greensand cirripedes ; to Dr. B. Pope Bartlett for 

 reporting on rock-specimens and fossils of UjDper Greensand and 

 Cenomanian age submitted for his opinion ; and to our colleagues 

 Mr. C. B. Wedd, for many helpful criticisms, and Mr. W. Manson, 

 for the skill and care with which he has prepared the drawings 

 for our illustrations. 



Carboniferous Fossils from Siam. 



By F. E. CowPER Eeed, M.A., Sc.D., F.G.S. 



(PLATE II.) ' 

 Introduction. 



IN 1899 the Cambridge Exploring Expedition to the Malay 

 Provinces of Lower Siam collected a few fossils and many 

 rock-specimens at a place named Kuan Lin Soh, in the Patalung 

 district. A small broken image of Buddha from the temple of Bah 

 Nah containing some similar fossils was considered to have been 

 quarried from the same beds, and it was believed that these 

 specimens represented strata of Cretaceous age.^ 



In the following year a brief report on the same material was made 

 by the late Professor T. McK. Hughes," and he was led to regard 

 the fauna as indicating the highest beds of the Carboniferous or the 

 Permo-Carboniferous, basing his conclusions on the following rough 

 determination of the fossils : " Proetus sp., encrinite stems and 

 arms, several species of lamellibranchs and brachiopods, including 

 at least one species of Chonetes, Pleurotomaria sp., and a cephalopod 

 with horse-shoe lobes." Special attention was paid to the litho- 

 logical characters of the rocks in which the fossils occurred, and 

 two types were recognized by Professor Hughes : (1) a grit of 

 varying coarseness without determinable fossils, and (2) a very 

 fine rock composed almost entirely of silica, with practically no 

 lime, but some alumina. 



It is the latter rock which has yielded the organic remains here 

 described, the coarser rock not having any recognizable fossils in it. 



The fossiliferous rock is of a curious and uncommon character, 

 having an argillaceous or even chalky appearance, though thin 

 sections and chemical analyses prove that it is almost entirely 

 composed of minute grains of silica. When fresh it is tough and 

 hard, with rarely a shaly and usually a subconchoidal fracture. 

 It is whitish in colour, but occasionally is stained yellow or pink. 

 It becomes soft and pulverulent when weathered and more or less 

 decomposed, with a chalky feel and aspect. 



1 This Plate will appear in the March issue. 



2 Report Brit. Assoc., Bradford, 1900, pp. 393-8. 

 ^ Report Brit. Assoc, Glasgow, 1901, p. 414. 



VOL. LVII. — NO. III. 8 



