.Chemistry and Physics. 



153 





LOWER EOCENE. 



MIDDLE EOCENE. 



UPPER EOCENE. 



OLIGOCENE. 



51 



Cerithium breviculum 

 Desk. 







Cerithium Boblayi 

 Desh. 



52 



Cerithium echidnoides 



Cerithium pleurotomoi- 







Lam. 



des Lam. 





53 Oerithium subacutum 





Cerithium Bouei Desh. 





1 d' Orb. 









54 Cerithium involutum 



Cerithium conoideum 



Cerithium Cordieri Desh. 





Lam. 



Lam. 







55 ^Cerithium plica tuluin 







Cerithium lunula 



Desk. 







Desh. 



56 Cerithium deceptor Desk. 



Cerithium perforatum 











Lam. 







51 



Cerithium turbinaturn 

 Desh. 



Cerithium interruptum 

 Lam. 







58 







Cerithium mixtum Desh. 



Cerithium con- 

 junctum Desh. 



59 





Rostellaria fissurella 

 Lam. 



Rostellaria lubrosa Sow. 





€0 





Buccinum sabrandei 



BucciDum Gottar- 









d' Orb. 



di Nyst. 



61 





Marginella crassula Desh. 



Marginella Edwardsi 

 Desh. 





€2 





MargineUa ovulata Lam. 





Marginella Stam- 

 pinensis St.-M. 



63 





Mitra cancellina Lam. 





Mitra perminuta 

 Brawn. 



64 





Yoluta spinosa Lam. 



Yoluta depauperataDesft,. 





65 





Oliva nitidula Desh. 



Oliva Baurnontiana Lam. 





66 





Aneillaria bucciuoides 

 Lam. 



Aneillaria obesula Desh. 





67 



Ringicula minor Desh. 



Ringicula ringens 

 Lam. sp. 



Ringicula ringens Lam. 

 (var. Meyer.) 





SCIENTIFIC INTELLIGENCE. 



I. Chemistry and Physics. 



1. On a new general Method for the Determination of Nitro- 

 gen. — The determination of nitrogen in nitro- and azo-compounds 

 is effected by the addition of some reducing material to the soda- 

 lime, by which the nitrogen is yielded as ammonia. Tamm- 

 Guyard proposed sodium acetate, Ruffler, sodium thiosulphate, 

 and Goldberg, stannous sulphide and sulphur. All these are 

 somewhat unsatisfactory as general methods, and Arnold has 

 experimented with a view to improve them. He first used a mix- 

 ture of acetate and thiosulphate, and afterward two or three per 

 cent of amorphous phosphorus ; but without advantage. He 

 then substituted sodium formate for the acetate, using it in con- 

 nection with sodium thiosulphate and soda lime, and obtained 

 excellent results. The combustion tubes used were from 10-12 



Am. Jour. Sci. — Third Series, Yol. XXX, No. 176, August, 1885. 

 10 



