CHAPTER XIX 



CONIFEROPHYTES— GNETALES— GNETUM 



The final genus in the gymnosperm phylum is Gnelum — in general 

 appearance almost as much out of place in this assemblage as Wel- 

 witschia, for most of its more than thirty species are lianas. Only a 

 few are trees or shrubs. 



In striking contrast with Ephedra and Welivitschia, both extreme 

 xerophytes confined to desert habitats, Gnetum belongs to the luxu- 

 riant tropics, and most of its species, when not in fruit, might be mis- 

 taken for dicotyls. 



Tropical Asia and the islands between Asia and AustraUa have 

 nineteen of the thirty-four species given by Pearson.''''^ The two 

 African species are north of the Welivitschia country, in Cameroons 

 and Angola. Of the twelve American species, three are in the Guin- 

 eas, along the northern coast of South America, seven belong to the 

 Amazon country of Brazil, one to Ecuador, and one to the West 

 Indies. There are none in North America, Australia, or Europe. 



No species have yet been found common to both Western and 

 Eastern hemispheres, but some in India and the islands between 

 India and Australia are found on both sides of the Equator. 



THE SPOROPHYTE — VEGETATIVE 



The lianas, which are characteristic of the genus, twine, climb, or 

 trail over other vegetation, reaching the tops of the tallest trees, 

 with rarely any leaves for the first 40 or 50 feet. Gnelum gncmon, in 

 the Moluccas, and widely cultivated, is a tree, and since it is the 

 best-known species, one is likely to picture the tree habit when one 

 thinks of Gnelum. A species in New Guinea, G. coslalum, also has the 

 tree habit; and there are also a few shrubs. 



The leaf. — The large, oval, entire leaves, with netted veins, make 

 the plants look like dicotyls. There are branches of limited and un- 

 limited growth, but the difference between the two kinds is not so 



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