1921] GOLDRING—CARBONIFEROUS WOOD 327 
Recently Berry has come into possession of part of a trunk of 
Cordaites from Bartlesville, Oklahoma, which shows annual rings 
of growth quite distinctly. The specimen comes from the Upper 
Pennsylvanian (below the Americus formation). The location is 
described as follows in a letter from the donor, Mr. GitBert Hart: 
As near as I can judge, the trees are confined to a rather limited belt, and 
are rather common there... . . The trees are found always below the Ameri- 
cus. As yet I have seen none surely in place; the nearest to the original 
position was in talus just below the first heavy limestone in the Admire forma- 
tion. I feel sure that this is almost the true horizon. 
The latitude of Bartlesville, Oklahoma, is 36°45’ N., about 10° 
south of the Prince Edward Island locality, practically the latitude 
of the Triassic forest of Arizona, where is found the coniferous wood 
showing more or less clearly marked annualrings. If the occurrence 
in Arizona argues for a “noteworthy variation in the annual 
temperature’? in this area during the Triassic, then the annual 
rings in the trees of the Oklahoma forest weve: indicate the same 
for the end of the Carboniferous. 
So far as known, the Oklahoma forest is the most southern 
occurrence of Carboniferous wood with annual rings of growth 
which has been noted; but such occurrences have previously been 
noted in wood from the Carboniferous, or earlier, in latitudes as 
far (or farther) south as Prince Edward Island. PENHALLOw,3 
in his discussion of North American species of Dadoxylon, states 
that, of the eighteen species now entitled to recognition, three 
show more or less clearly defined growth rings, while in the remain- 
ing fifteen they are obscure or obsolete. Of the species discussed 
in this paper one, Cordaites pennsylvanicum (Dawson) Penhallow, 
showing distinct growth rings, comes from the Carboniferous at 
Pittsville, Pennsylvania (41°30’ N.). Two other species, C. Hamil- 
tonense Penhallow and C. Clarkii Dawson from the Devonian 
(Genesee shales) of Ontario County, New York (43°N.), show 
obscure growth rings. In the second species, however, they are, 
sometimes wanting. Both the Pennsylvanian and New York 
localities are much farther south than the English (54° N.) or 
Prince Edward Island (46° N.) areas. 
3 Trans. Roy. Soc. Can. 6:57. 1900. 
