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Scientific Proceedings ^ Royal Dublin Society. 



to North America or to East Asia, it flourished at one time in Europe, 

 and fell before a lowered temperature and other adverse conditions. 

 C. and E. M. Eeid (2) describe and illustrate a cone from the Pliocene beds 

 on the Dutch-German border as probably the last trace of Sequoia in 

 Europe. E. W. Berry (.3) gives a useful map (fig. 1) showing the almost 

 world-wide distribution of Sequoia during the Tertiary epoch, in striking 

 contrast to its present restricted area. Its occurrence in New Zealand, 

 South-East Australia, and South America, the only localities recorded by him 

 in the Southern Hemisphere, is worthy of note, and seems in need of critical 

 confirmation. West and Central Europe, North-East Asia, North America, 

 and the Arctic regions were its chief centres. 



Sketch Map showing the location of Caenozoic records of Sequoia. 

 After Berry, from " The Plant World." 



It will be well to state here the distinguishing characters of the foliage 

 of the living species of Sequoia for comparison with fossil forms. In both 

 species the leaves are mostly spirally arranged, and more or less clearly 

 decurrent. In- S. semjiervirens the base of the leaf is so twisted that the leaves 

 appear distichously arranged. They are yew-like, linear, and flattened, 

 with a single vein as midrib. The apex may be acute or obtuse. In 

 S. gigantea the spiral arrangement is undisturbed and obvious, the leaves 

 narrow and subulate, roughly three- or four-sided (rhomboidal), with one vein. 

 They are more or less adnate or adpressed in their lower part, spreading above. 

 Their ridged bases are so decurrent and close together as to cover the whole 

 surface of the stem, thus leaving no part of the stem surface proper exposed. 

 Further, in both species there are small ovate-triangular, squamiform, keeled, 

 closely adpressed, spirally arranged leaves. Thus both species are dimorphic. 

 The squamiform leaves occur on the coire-bearing shoots in both species, and 

 at intervals on the foliage shoots of S. gir/antea. They occur in 5". sem^ervirens 

 also at the tips of the foliage shoots, making its buds " scaly " in contrast to 



