612 REVISION OF ARAUCARIOXYLON KNOWLTON. 



15. Dadoxylon Rollei Ung. 



Unger, Der Yersteint. Wald b. Cario, u. s. w., Sitzb. d. mathem-naturw. CI. 



d. Akad. zu Wien, Vol. xxxm, 1858, p. 230, PI. n, figs. 6-8. 

 Araucarites Rollei CUng.) Goppert, Foss. Fl. d. Perm. Form., p. 250. 



Concentric circles even, obscure; tracheids ample in size, thick- 

 walled, provided with two to three series of small, strictly contiguous 

 pores ; medullary rays simple or partly composed of two series of two 

 to forty superimposed cells. (Unger.) 



Permian formation, Erbstadt near Bonstadt in the Wetterau. 



16. Dadoxylon Richteri Ung. 



Unger, Der Versteint. Wald b. Cario, u. s. w., Sitzb. d. ruatheru-naturw. CI., 



d. Akad. Vol. xxxm, 1858, p. 230, PI. n, figs. 9-11. 

 Araucarites Richteri (Ung.) Goppert, Foss. Fl. d. Perm. Form., p. 251. 



Concentric circles even, obscure; tracheids narrow, thick- walled, 

 provided with one to two or three series of small subcontiguous pores ; 

 medullary rays simple, composed of one to eighteen superimposed 

 cells. (Unger.) 



Permian formation, Saalfeld in Thuringia. 



17. Dadoxylon Saxouicum Geinitz Sp. 



Araucarites Saxonicus Geinitz. Leit. pfl. d. Rothrieg., p. 25; Goppert, Foss. FL 

 d. Perm. Form., p. 251, PI. liv ; lv ; lvi, figs. 2-4; lx, figs. 1, 2. 



Concentric circles distinct ; trachei'ds large, provided with five series 

 of spirally disposed, hexagonal pores ; medullary rays in a single series 

 of five to thirty superimposed cells. (Goppert.) 



Permian formatiou, Saxony. 



18. Dadoxylon pachytichum GOpp. Sp. 



Araucarites pachytichus Goppert. Foss. Fl. d. Perm. Form., 1864-65, p. 257, PL 

 lvii, figs. 6-9. 



Concentric circles distinct ; tracheids with the walls so thick as to 

 almost obliterate the lumen ; walls provided with three to five series 

 of hexagonally compressed pores ; medullary rays composed of a single 

 series of from five to twenty cells. (Goppert.) 



Permian formation, Saxony. 



19. Dadoxylon Rhodeanum Gopp. Sp. 



Araucarites Rkodeanus Goppert in Wimraer. Fl. von Schlesien, Vol. II, p. 218;. 

 Monog. d. Foss. Conif., 1850, p. 235, PI. xliii, figs. 6-7; Foss. Fl. d. Perm. 

 Form., 1864-'65, p. 256, PI. lvii, figs. 1-5. 



Concentric circles evident ; tracheids moderately thick walled, pro- 

 vided with one to two series of contiguous pores ; medullary rays sim- 

 ple, of one to many cells superimposed. (Goppert.) 



Permian formation, Silesia. 



