JOUENAL 



OF THE 



KOYAL MICROSCOPICAL SOCIETY, 



FEBRUARY, 1910. 



TRANSACTIONS OF THE SOCIETY. 



I. — On the Microscopical Structure of an Inoceramus Limestone 

 in the Queensland Cretaceous Bocks. 



By Frederick Chapman, A.L.S., F.E.M.S. 



( Read November 17, 1909.) 

 Plate I. 



Prefatory. — The occurrence of a rock largely composed of the 

 remains of Inoceramus shells in the Lower Cretaceous of Queens- 

 land is by no means new. The interest attaching to it, however, 

 especially from a penological point of view, will justify a fuller 

 description than has yet been given. 



In Messrs. Jack and Etheridge's valuable and comprehensive 

 work on " The Geology and Palaeontology of Queensland and New 

 Guinea," * Mr. Jack makes the following observations (p. 400) : — 

 " Eight miles beyond the Williams [River] are blocks of a very hard 

 brecciated siliceo-calcareous stratified rock, from which I obtained 

 Inoceramus. Portions of the rock were almost entirely made up of 

 the disintegrated shelly fibres of this genus." Further, the same 

 author remarks (p. 401) : — " Fifteen miles from the Williams (on 



* Brisbane and London, 1892. 



EXPLANATION OF PLATE I. 



Fig. 1. — Inoceramus limestone, viewed at right angles to the bedding plane ; show- 

 ing current bedding. About natural size. 

 ,, 2. — Surface of bed-plane, showing fragments of Inoceramus shell and numerous 



shell-prisms. About natural size. 

 ,, 3. — Section parallel with bed-plane, showing constitution of the Inoceramus 

 limestone, shell-prisms and angular quartz-grains imbedded in a 

 calcareo-ferruginous matrix, x 18. 



Feb. 16th, 1910 B 



