A REVISION OF THE GENUS ARAUCARIOXYLON OF KRAUS, WITH 

 COMPILED DESCRIPTIONS AND PARTIAL SYNONYMY OF THE 

 SPECIES. 



Assistant Curator of the Department of Fossil Plants. 



Having recently bad occasion to identify several species of fossil 

 wood showing the Araucaria like structure from the Potomac forma- 

 tion of Virginia,* the Jurassic of Arizona and New Mexico,t and the 

 Devonian of New York, considerable difficulty was experienced in 

 readily referriug to the published descriptions and figures. As a 

 matter of personal convenience a card index was prepared, containing 

 references to the principal descriptions and illustrations. The prepara- 

 tion of this index suggested the idea that other workers in the same field 

 must have experienced similar needs, and this has led to its expansion 

 into the following partial revision and description of the accepted 

 species. 



The literature of the subject may be said to date from the publica- 

 tion of Witham's work on the "Internal Structure of Fossil Vegeta- 

 bles," which appeared in 1832. From that time until the present more 

 than fifty species have been established, the descriptions and figures 

 of which are scattered through various foreign periodicals, or occur in 

 the systematic works of Dawson, Goppert, U tiger, Kraus, Felix, and 

 others. From these sources the principal synonymy has been com- 

 piled, together with the description of the species. 



The first systematic enumeration of species was that given by End- 

 licher in 1847 in his "Synopsis Couiferarum." He there describes four- 

 teen species that have since been referred to the Araucarian type. 

 Unger, in his "Genera et Species Plantarum Fossiliuin," published in 

 1850, enumerates about the same number of species. The most exten- 

 sive compilation is that given by Kraus in Schimper's "Traite de 

 Paleontologie Vegetale," Vol. II, published in 1870-'72. He here estab- 

 lished the genus Araucarioxylon, and gives a list of thirty-two species 

 derived from the older genera Araucarites, Dadoxylon, Pissadendron, 

 etc. None of these species are accompanied by descriptions, and the 



* Bull. U. S. Geol. Survey, No. 56, p. 50, PI. vn, figs. 2-5. 

 tProc. U. S. Nat. Mns., 1886, pp. 1-4, PI. I. 



Proceedings National Museum, Vol. XII — No. 784. 



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