V °l889"'] PROCEEDINGS OF THE NATIONAL MUSEUM. 613 



20. Dadoxylon Fleurotii Mougeot Sp. 



Pinites Fleurotii Mougeot Essai d'une Flore du Nouv. gres rouge d. Vosges, 



1851, p. 26, PL in, figs. 2-5. 

 Araucarites Fleurotii (Moug.) Goppert. Foss. Fl. d. Perm. Form., 1864-'65, p. 



257. 



Concentric circles distinct; tracheids narrow, provided usually with 

 a single row of contiguous angular pores, sometimes with two rows of 

 alternating pores ; medullary rays in a single series of from four to six 

 superimposed cells. 



21. Dadoxylon Fermicum Merckl. Sp. 



Araucarites Permicus Mercklin. Paleodeudrol. Ross. 1856, p. 53, PL x, figs. 

 6-10 ; Goppert, Foss. Fl. d. Perm. Form., 1864-'65, p. 258. 



Concentric circles broad, irregular, scarcely distinct; tracheids am- 

 ple, usually six-sided, thin walled, provided with two to four, rarely 

 five, series of contiguous, hexagonal pores, with minute inner pores; 

 medullary rays equal, thick, many-pored, simple, composed of one to 

 twenty, rarely forty, or more superimposed cells. (Mercklin.) 



Permian formation, Eussia. 



22. Dadoxylon cupreum Gopp. Sp. 



Araucarites cupreus Goppert. Monog. d. Foss. Conif., 1850, p. 233, PL xliii, 

 figs. 2-4 ; Foss. Fl. d. Perm. Form., 1864-'65, p. 258. 



Concentric circles nearly obsolete; tracheids ample, moderately thin 

 walled, provided with one to two series of spirally arranged pores ; 

 medullary rays rlexuous, composed of a single series of from one to ten 

 large cells. (Goppert.) 



Permian formation, Western Urals. 



23. Dadoxylon biarmicus Kutorga Sp. 



Peuce biarmica Kutorga, Verhandl. d. k. minerolog. GeselL, zu St. Petersburg, 



1842, p. 9-11, PL ii, figs. 4, a, b, c, d. 

 Araucarites Kutorga Mercklin. Paleodeudrol. Ross, 1856, p. 56; Goppert, Foss. 



Fl. d. Perm. Form., 1864-'65, p. 258. 



Concentric rings distinct; tracheids large, six-sided, thin walled, 

 provided with one, rarely two, series of small four to six augled pores; 

 medullary rays in a single series of from four to ten superimposed cells. 

 (Goppert.) 



Permian formation, Gov. Perm, Russia. 



