THE FOSSIL OSMUND A CEJE. 661 



xylem strand is usually very stout, as shown in fig. 55, which may be regarded as a 

 diarch root, although there are strong indications of a third protoxylem. In fact, it is 

 probable that both types of structure occur at different points in the same root. In 

 other roots the diarch xylem strand is very much thinner, and these are probably 

 lateral branches. The cortex of the root is entirely sclerotic, the size of the cells in- 

 creasing somewhat from the endodermis outwards. 



Locality. — Mine Kloutschewsk, district of Bjelebei, government of Orenburg, 

 Russia. 



Horizon. — Upper Permian, " gres cuivreux" (cf. P 2 of Geological Table, Part II., 

 p. 219). 



Anomorrhoea, Eichwald. 



I860. Eichwald, Lethsea Rossica, vol. i., p. 102. 



Anomorrhoea Pischeri, Eichwald. 

 (PI. VIII.) 



I860. Anomorrhoea Fischeri, Eichwald, Lethsea Rossica, vol. i., p. 102, pi. iv. figs. 3 and 4. 

 1869. Anomorrhoea Fischeri, Schimper, Traite d. paleonl. veget., vol. i., p. 702. 



The original specimen of Anomorrhoea Fischeri was figured by Eichwald in his 

 Lethaea Rossica, pi. iv. figs. 3 and 4, and is again represented about natural size 

 in PI. VIII. fig. 57 of the present paper. The fossil consists only of a certain thick- 

 ness of the coating of petiole bases that originally surrounded the stem, to which small 

 fragments of the outer cortex are still adhering at some points. The outer surface of 

 the fossil shows the obliquely fractured ends of the almost vertically growing petioles 

 in the form of closely packed elongated rhomboidal scars. 



in some of the transverse sections of our material, which was cut from the upper 

 end of the type specimen, closely packed petiole bases alone are to be seen (fig. 58). 

 In others the structure of the inmost leaf-traces is such that they must have been 

 situated in the cortex of the stem (fig. 59, C). Most of the tissues of this cortex have 

 entirely disappeared, but no doubt it consisted almost entirely of the inner parenchy- 

 matous zone. It appears, therefore, that in this stem the outer sclerotic cortex is 

 practically absent, being reduced to a narrow zone consisting merely of the confluent 

 sclerotic rings of the petioles. Only the xylem strand of the leaf-trace is preserved in 

 the inner cortex, and in longitudinal section it is seen to consist of tracheae with the 

 usual multiseriate pitting. In the inmost traces the xylem strand is only slightly 

 curved, and it possesses a single median endarch protoxylem strand (fig. 60). In those 

 farther out the protoxylem divides into two (fig. 61), subsequently into three (fig. 62), 

 and at the same time the curve of the xylem strand gradually increases until, when it 

 enters the free petiole, it has taken up the form of an arch (fig. 63). In the outer region 

 of the cortex the leaf-traces are sometimes accompanied by a few sclerotic elements. In 



