S46 Mr Haidinger on Poly halite. 



nulla. Filamenta quinque, calycis laciniis opposita, hisque 

 duplo longiora, subulata, glabra. Antherae magnae, rufescentes, 

 cordatae, emarginatae. Germen superum, ovatum. Stylus nul- 

 ius. Stigmata tria acuta. 



Calyx fructiferus orbiculatus, clausus, depressus, quinque- 

 sulcus, carnosiusculus. Receptaculum totum fere calycem im- 

 plens, carnosum. Semen unicum in receptaculo nidulans hori- 

 zontale, suborbiculatum, nitidum, niargine acuto hinc mucro- 

 nato cinctum. Albumen centrale. Embryon teres, incurvum, 

 hori zontale. Cotyledones semiteretes. Radicula centrifuga. 



The habit or general appearance is very different from that 

 of the Palak ; and, as the seed is only immersed in a pulpy 

 receptaculum, and not entirely covered by it, the Palak and 

 Nunika may be placed in different genera. The leaves and 

 tender shoots of the latter have an agreeable saline taste ; but 

 it is not used by the natives. 



Art. VII. — On Polyhalite. By William Haidinger, Esq. 

 F. R. S. E. &c. Communicated by the Author. 



The species of polyhalite was established by chemical analysis 

 from such varieties as would not allow of a complete determi- 

 nation according to the principles of natural history, since they 

 presented nothing but fibrous masses, without a trace of regu- 

 lar structure or crystallization. It is not to be wondered, there- 

 fore, that it should have been hitherto considered as a more or 

 less problematical substance, and exhibited as such in the ap- 

 pendices of most of our systems, even in those which pretend 

 to proceed according to chemical views, the only thing known 

 in the present instance. It was doubted whether the many 

 salts contained in it, from which circumstance Stromeyer de- 

 rived the name polyhalite, were in actual chemical combination, 

 or whether they formed but a mechanical aggregate, and we 

 must allow that this is a fair enough view of the subject, if we 

 consider the results which he obtained, viz. 



Sulphate of potassa 27.7037 Muriate of magnesia 0.0100 



lime 44.7429 Protosulphate of iron 0.2927 



magnesia 20.0347 Water - - 5.9535 



Muriate of soda 0.1910 Peroxide of iron 0.3376 



