1853.] Report on the Geological Structure of tlie Salt Range. 349 



the bottom of which a large hole has been made, is then put on 

 the top of the lower one, and secured to it by a coating of clay, to 

 which succeeds a third and a fourth, all communicating with each 

 other. A sharp wood fire is then lighted under the lower gurrah, 

 by which the sulphur is gradually sublimed in the form of flowers of 

 sulphur into the upper ones, to the sides of which it adheres. The 

 subliming process generally goes on for eight or ten hours, by which 

 time all the sulphur has been expelled from its matrix. 



None of the organic remains which occur in the nummulite lime- 

 stone formation have been detected in the rocks inferior to it. The 

 mulluscse which characterize it have a totally different character, and 

 neither belemnites, ammonites, nor terebratulse which occur in the 

 oolitic rocks beneath are to be seen, their place being taken by 

 swarms of Foraminifera of the genera Nummulina and Fascialites ? 

 and by large Gasteropoda of the genera Conus, Trochus, Oliva, Mitra, 

 Voluta, Terebellum, Natica, Acritina, &c. 



Several large bivalves also occur, and a small Ostrea (?) forms in 

 some places patches of yellow marly limestone. 



The abundance of nummulites is very remarkable ; and at least two 

 or three species occur. They have of late years been considered as 

 characteristic of formations superior to the chalk, and as regards 

 the Alps where the nummulite limestone is so extensively developed, 

 Sir Roderick Murchison, in his paper above quoted, says, " I am 

 persuaded that no form of the genus JNummulina occurs below the 

 surface of the chalk, or its equivalent," and again, " that the lowest 

 beds with nummulites are completely above all those rocks which 

 are the equivalent of the white chalk of northern Europe." 



Cephalopoda seem very scarce. We have only obtained speci- 

 mens of two large species of nautilus. 



Eadiata are in some places rather plentiful, and specimens of spe- 

 cies of the genera Spatangus, Gralerites and Clypeaster have been 

 procured ; some of the former are of large size. 



The only indication of vertebrata we have obtained, are a few 

 teeth, evidently those of sharks, and one or two small fragments of 

 bone too indistinct, however, we fear, to be identified. 



The fossils, except in the calcareous sandstone, are generally ill-pre- 



2 x 



