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ZA'FFEE. An impure oxide of cobalt, 

 obtained by roasting the ore of 

 cobalt, by which process the arsenic 

 and sulphur contained in the ore 

 are driven off. Zaffre melted with 

 silex and potash, and reduced to 

 powder, constitutes the article 

 known under the name of powder 

 blue. So intense is the blue 

 afforded by Zaffre, that one grain 

 will give a full blue to 240 grains 

 of glass. 



ZA'MIA. A genus of the class Appen- 

 dix palmse, Dioecia, order Polyan- 

 dria, natural order of Palmse, Fili- 

 ces (Juss). Generic character: 

 Male, calyx ; ament strobile- 

 shaped, ovate, obtuse ; scales hori- 

 zontal, pellate, obovate, very blunt, 

 one-flowered, thickened at the top, 

 permanent. Corolla none. Sta- 

 mina : filaments none. Anthers 

 subglobular, clustered, accumulated 

 in the lower surface of the scales, 

 sessile, two-valved, opening above 

 by a longitudinal cleft. Pollen, 

 farinaceous. Female, calyx ; 

 ament strobile- shaped, larger, ovate, 

 imbricate; scales pedicelled, pellate, 

 angular, finally distant, permanent. 

 Corolla none. Pistil : germs two, 

 irregular, angular, inserted into the 

 margin under the pelta of the scales, 

 solitary on each side, nodding. 

 Style none. Stigma obtuse, ob- 

 scurely cloven at the side. Peri- 

 carp: " berries to each scale two 

 ovate, barked at the base, fleshy, 

 one-celled. Seed one in each berry, 

 ovate. Essential character: Male, 

 ament strobile-shaped, scales cov- 

 ered with pollen underneath. 

 Female, ament strobile-shaped, 

 with scales at each margin ; berry 

 solitary. 

 Fossil zamise have been disco- 



vered in the coal formation, and in 

 the Wealden formation at Yaver- 

 land, on the south coast of the Isle 

 of Wight. 



ZA'MITE. A fossil zamia. M. Ad. 

 Brongniart has referred the zamite, 

 or fossil zamia, to a new genus, to 

 which he has assigned the name of 

 Mantellia nidiformis. 

 ZECH-STEIN. | (The Magnesian Lime- 

 ZETCHS*EIN. j stone of English; Cal- 

 caire Alpen of French ; the Alpen- 

 kalkstein of German Geologists. 

 The name Zechstein was given to 

 this formation by Humboldt.) The 

 second member of the red sandstone 

 series, in the ascending order. The 

 zech-stein is a calcareous deposit, 

 or magnesian limestone, of a some- 

 what variable aspect ; it is fossili- 

 ferous, and in it, as far as observa- 

 tions have yet gone, are found, 

 for the first time, those shells known 

 by the name of Products; Spirifera 

 also now are found, for the first 

 time, in the descending series; 

 these and Productse both abound- 

 ing in the Carboniferous Limestone. 

 The organic character of the zech- 

 stein, as far as the researches of 

 geologists have hitherto gone, near- 

 ly approaches that of the carboni- 

 ferous group, a circumstance which 

 will greatly tend to add to the 

 difficulty of determining between 

 the zechstein and the carboniferous 

 limestone, when their geological 

 position cannot be ascertained with 

 certainty. Some geologists are of 

 opinion that the connection between 

 the two formations of red sandstone 

 and zech-stein is so intimate, that 

 the latter may be regarded as a 

 subordinate formation to the former. 

 The zech-stein lies immediately 

 under the new red sandstone and 



