New Brunswick, Maine, and Eastern Canada. 165 



1. Dadoxylon Ouangondianum,^ — Sp. nov. 



Fig. 2. 



Figs, land 2. — Dadoxylon Ouangondianum. 

 Fig. 1. — Transverse section 50 diams. («) Wood cells, (b) Line of 

 growth. 



Fig. 2. — Longitudinal section, radial, (a) Disc structure. (6) Me- 

 dullary rays. 



Description. — Branching trunks, with distinct zones of growth, and a 

 pith of Sternbergia type. "Wood cells very large, with three to five 

 rows of contiguous alternate hexagonal areoles with oval pores. 

 Medullary rays with one to three series of cells, and as many as 14 

 rows of cells superimposed on each other. 



Trunks of this fine coniferous tree are not infrequent in the 

 St. John sandstones explored by Mr. Matthew. They retain 

 their structure in great perfection, especially in silicified speci- 

 mens. Some of the trunks have been a foot or more in diameter. 

 They show traces of growth rings on their weathered ends, and 

 when perfect, are traversed by the transversely wrinkled pith 

 cylinders, formerly known as Sternberg ioe. Under the microscope 

 the wood cells are seen to be of remarkable size, being fully 

 one-third laro-er in their diameter than those of P'lnus strohus or 

 Araucaria Cunning hami, and also much larger than those of the 

 ordinary coniferous trees of the coal measures. They are beauti- 

 fully marked with contiguous hexagonal areoles, in which are in- 

 scribed oval slits or pores, placed diagonally. The medullary 

 rays are large and frequent, but their cells, unlike the wood cells 

 (prosenchyma), are more small and delicate than those of the trees 

 just mentioned. The pith w^hen perfectly preserved, presents a 



* I have named this species after the ancient Indian designation of 

 the St. John River, Ouangonda. I use the generic term Dadoxylon as 

 probably best known to English geologists ; but I sympathise with 

 Goeppert in his preference of the generic term Araucarites for such 

 trees. 



