182 CONIFERALES [CH. 



Medullary rays uniseriate, reaching a depth of 30 cells, 2 4 

 elliptical oblique pits in the field ; wood-parenchyma, often with 

 dark contents, is not uncommon. Gothan emphasises the abund- 

 ance of xylem-parenchyma as a character in which this species 

 differs from typical Dadoxylons. 



Dadoxylon mahajambjense (Fliche). 



Fliche 1 described this species, from Liassic strata in Madagascar, 

 under the name Araucarioxylon : the radial walls of the tracheids 

 have two rows of contiguous and alternate pits; the medullary 

 rays are uniseriate, usually 8 16 cells deep, and small circular 

 pits occur on the radial walls. 



Dadoxylon divescence (Lignier). 



An Oxfordian species from Normandy characterised by leaf- 

 traces larger than those of Araucaria imbricata and, as Lignier 2 

 states, suggesting leaves comparable in size with those of Cordaites. 

 The tracheids have 1 4 rows of pits and the medullary rays are 

 8 11 cells in depth. 



Dadoxylon argillicola (Eichwald), recorded from Moscow 3 , is 

 another example of a similar type of wood, and many other in- 

 stances might be quoted in illustration of the wide distribution 

 of vegetative organs in Jurassic beds agreeing anatomically with 

 the Araucarineae. 



Dadoxylon (Araucarioxylon) novae zeelandiae* (Stopes). 



A Cretaceous species from Amuri Bluff, New Zealand 5 , founded 

 on a piece of decorticated stem 8 cm. in diameter preserved partly in 

 silica and in part in a calcareous medium. The small pith, not more 

 than 1 mm. in diameter, is imperfectly petrified: the tracheids 

 of the secondary xylem, which shows well-marked annual rings, 

 have biseriate, alternate, hexagonal, pits ; there is no xylem-paren- 

 chyma. An interesting feature is the occurrence of tracheids on 

 each side of the medullary rays with thicker walls and containing 

 discs of resin : these resiniferous tracheids, similar to those de- 

 scribed by Thomson 6 and other authors, afford particularly good 



1 Fliche (05) p. 350, PI. x. fig. 1. 



2 Lignier (07 2 ) p. 257, PI. xvn. figs. 1013. 3 Eichwald (68) PI. v. fig. 12. 



4 The .'pecific name is given by Dr Stopes as novae ztelandii. 



5 Stopes (14 2 ) PI. xx. 6 Thomson, R. B. (13). 



