176 MORPHOLOGY OF SPBRMATOPHYTES 



GINKGOALBS 



This phylum, once with a very extensive range, is nov7 repre- 

 sented by a single species, which is restricted to China and 

 Japan. It was formerly supposed that even this species had 

 long ceased to exist in the wild state, but specimens which seem 

 to be undoubtedly wild have been reported from China and 

 Japan. 



CONIFEEALES 



While Cycads are tropical forms, Conifers belong as dis- 

 tinctly to temperate regions, forming vast forest areas, especially 

 in the northern hemisphere. A map indicating their general 

 distribution would show a heavy north temperate massing, and 

 a lighter south temperate massing, the two separated from one 

 another by a broad tropical belt, traversed in but two places — 

 namely, the East Indian region and the Andean region. These 

 northern and southern masses contain mostly what are regarded 

 as different generic types. Firms dominating at the north, and 

 PodocarpiLS at the south. Through the East Indian region 

 Podocarpus reaches China and Japan ; while the northern genus 

 Libocedrus reaches Australia by the same route, and penetrates 

 far into temperate South America by way of the Andes. Aside 

 from these two lines of communication, and these two genera, 

 there is no crossing of the tropics, all other genera being ex<5lu- 

 sively northern or southern. 



Before considering the main groups in some detail, it 

 may be well to note a few facts of general interest. By far 

 the greatest Conifer display in genera and species is that which 

 borders the Pacific Ocean, the chief areas being the China- 

 Japan region, the Australasian region, and western North 

 America; while the whole of this vast border region is occu- 

 pied by Libocedrus. 



The most remarkable displays of endemic genera are found 

 in the China-Japan and the Australasian regions, the former 

 containing Cephalotaxus (4 spp.), Pseudolarix (1 sp.), Kete- 

 leeria (2 spp.), SciadopHys (1 sp.), Cunninghamia (1 sp.), 

 Gryptomeria (1 sp.), Glyptostrohus (2 spp.), Thujopsis (1 

 sp. ) ; while the latter contains Microcachrys (1 sp. ) , Phyllo- 

 cladus (3 spp.), Agathis (4 spp.), Arthrotaxis (3 spp.), and 



