HABIT AND STRUCTURE OF CYCaDE^. 369 



land plants in the Secondary formations, (from the Keuper 

 to the Chalk inclusive ;) one half of these are Coniferse and 

 Cycadas, and of this half, twenty-nine are Cycadese; the 

 remaining half are chiefly vascular Cryptogamise, viz. Ferns, 

 Equisetaceffi, and Lycopodiacese. In our actual vegetation, 

 Coniferse and Cycadeae scarcely compose a three hundreth 

 part.* 



The family of Cycadese comprehends only two living 

 Genera; viz. Cycas, (PL 58.) and Zamia. (PI. 59.) There 

 are five known living Species of Cycas and about seventeen 

 of Zamia. Not a single species of the Cycadeae grows at the 

 present time in Europe: their principal localities are parts 

 of equinoctial America, the West Indies, the Cape of Good 

 Hope, Madagascar, India, the Molucca Islands, Japan, 

 China, and New Holland. 



Four or five genera, and twenty-nine species of Cycadeas, 

 occur in the fossil Flora of the Secondary period, but 

 remains of this family are very rare in strata of the Transi- 

 tion, and Tertiary series.f 



* The fossil vegetables in the Secondary series, although they present 

 many kinds of Lignite, very rarely form beds of valuable Coal. The imper- 

 fect coal of the Cleaveland Moorlands near Whitby, and of Brora in Sutherland, 

 belong to the inferior region of the Oolite formation. The bituminous coal 

 of Buckeberg near Minden, in Westphalia, is in the Wealden formation. 



The coal of Hoer in Scania is either in the Wealden formation, or in the 

 Green-sand (Ann. des Sciences Nat. torn. iv. p. 200.) 



t I learn by letter from Count Sternberg, (Aug. 1835.) that he has found 

 Cycadese and Zamites in the Coal formation of Bohemia, of which he will 

 publish figures in the 7th and 8th Cahier of his Flore du Monde primitif. 

 This is, I believe, the first example of the recognition of plants of this 

 family in strata of the Carboniferous series. 



During a recent visit to the extensive and admirably arranged geological 

 collection in the Museum at Strasbourg, I was informed by M. Voltz that 

 the stern of a Cycadites in that museum, described , by M. Ad. Brongniart, 

 as a Mantellia, from the Muschelkalk of Luneville, is derived from the Lias 

 near that Town. M. Voltz knows no example 'of any Cycadites from the 

 Muschelkalk. Stems and leaves of Cycadese occur also in the Lias at Lyme 

 Regis. (Lind. Foss. Fl. Fl. 143.) 



