0. C. Marsh on the Remains of a new Enaliosaurian. 13 



The quantity of sulphur contained in the substance was not 

 estimated directly ; but was calculated from the amount of cop- 

 per present, with which it was united in the form of copper 

 pyrites, as ascertained by the preliminary examination. The 

 alumina was estimated by deducting the amount of the other 

 ingredients from the weight of the two ammonia precipitates. 

 The manganese, magnesia, chlorine, fluorine, and sulphuric acid 

 were not present in sufficient quantities to admit of accurate 

 determination. 



A second portion of the original substance was dried at 100° 

 C. until the weight became constant, and the loss estimated as 

 water. The remaining anhydrous substance was next ignited 

 at a red heat for some time in an open crucible; and when it 

 ceased to lose weight, the organic matter* which it had contained 

 was estimated from the loss, after deducting the amount of the 

 carbonic acid and the sulphur, which had also been expelled. 

 The residue was then treated with chlorhydric acid, the solu- 



s the 

 traces ot manganese, magnesia, and fluorine in the filtrate, were 

 then removed by ammonia. The precipitate thus obtained was 

 redissolved in chlorhydric acid, and the quantity of iron con- 

 tained in it determined vol u metrically by permanganate of pot- 

 ash. The filtrate from the ammonia precipitate was next evapo- 

 rated to dryness and gently ignited to remove the ammonia 

 salts, and then treated with hydrate of lime. From the filtrate 

 which remained the potash and soda were obtained in the usual 

 manner, and first weighed together as chlorids : they were then 

 redissolved, and their respective amounts calculated from the 

 quantity of chlorine in the solution, which was determined volu- 

 metrically by nitrate of silver. 



In a third portion of the original substance the carbonic acid 

 was estimated in the usual way, from the loss of weight after 

 treatment with dilute chlorhydric acid. 



The material taken for analysis was part of a segment from 

 the lateral surface of the vertebra, which remained after pre- 

 paring the microscopic sections. The following were its physical 

 characters: Compact, with uneven fracture. Hardness, 3-5. 

 Specific gravity at 20° C, 2-78. Lustre dull. Color brown. 

 Opaque. 



* It is not unlikely that a portion of the loss by 

 pelled below the faeat of ignition. 



