24 



BRITISH EOCENE ELORA. 



difference in size between the Haring, Radaboj, and Armissan specimens of C. Brong- 

 niarti, and still smaller specimens from St. Zacharie are described as C. Heerii. 



C. Brongniarti (Goeppert, 1836') is closely related to the existing C. quadrivalvis ; 

 and is highly characteristic of the later Eocenes and Oligocene of Central Europe, for it 

 appears to have grown on all the shores of the Eocene Mediterranean Sea. Its area has, 

 according to Saporta," become more and more circumscribed, until at the present day it 

 seems to have taken refuge only in the most southern portions of its former habitat, the 

 existing species being now confined to the Mountains of Barbary and Mount Atlas. It 

 loves rocky situations and a warm dry climate in proximity to the sea, and Saporta hence 

 infers that the Eocene climatic conditions of Aix resembled those of Barbary or 

 Abyssinia. There can hardly be a doubt but that the humidity of climate, evidenced by 

 the flora, excluded it during the middle and later Eocene periods from the British area. 



Genus — Libocedrus. 



The genus Libocedrus is readily distinguished by its small, flattened, ovate, or 

 oblong cone, composed of four to six hard leathery valves, very unequal, and in opposite 

 pairs, not overlapping, and with small recurved terminal points. These cones are 

 deciduous, and have not 3'et been met with fossil. The flowers are separate and 

 terminal, and the seeds winged and samaroid, the valves of the cone remaining widely 

 gaping. The foliage is no less characteristic, being thick and scale-like, and the leaves 

 compressed in opposite pairs, and regularly imbricated in four rows. The genus, which 

 occasionally forms very large trees, is widely distributed, two species being met Avith in 

 Chih, two in New Zealand, and the rest in China, Japan, and California. Most of these 

 grow at considerable altitudes, some even reaching the snow-line. Only three fossil 

 species have been described, two of them from the Tertiaries. Of these L. salicornioides, a 

 very characteristic species, has been met with in the Tongrian at Armissan, Menat, &c., at 

 Bilin, Radaboj, Schoenegg, Leoben in Styria, in Austro-Hungary, at Bonn, and in the 

 amber-beds of Prussia, Monod in Switzerland, and Sinigaglia in Italy. It is compared 

 to L. cJdlensis. Another species has been recognised by Heer in the Eocene of Spitz- 

 bergen, and appears to resemble L. andina, a tree confined to the cold valleys of the 

 Andes. There is some evidence of a second and larger Arctic species, but the material 

 is hardly satisfactory. The remaining species is from the Upper Cretaceous of Greenland, 

 whence a very singular and apparently allied genus, Moriconia, has also been obtained. 



1 It first appears in the Calcaire Grossier of the Trocadero and Arcueil, near Paris, at Aix, St. 

 Zacharie and Armissan (Saporta), and at Haring, Radaboj, Schossnitz, Sagor, Koumi ; its most northerly 

 range having been Salzhausen, in the Wetterau, latitude 51° 24'. The foliage in most localities is 

 abucdant, and the fruit often attached. 



2 " Kevision des Floras d'Aix," 'Ann. des Sciences Nat.,' 5 serie; ' Botanique,' vol. xv, 18/2, pp. 39, 

 50—53. 



