172 Rhodora [SEPTEMBER 
represent somewhat modified traumatice resin-canals. As the rays 
cross the wounded area, their cells become thick-walled and pitted. 
5. Paracedroxylon is another primitive Araucarian, on the border 
line between this group and their ancestors, the primitive A bietineae. 
It probably left the ascending Araucarian line before the appearance 
cf flattened pitting. Its traumatic canals were subsequently much 
reduced from the typical Abietineous condition. 
б. ‘The presence of Paracedroxylon in the Second Cliff clays makes 
it probable that they are of Cretaceous origin, 
I desire to express my sincere thanks to Prof. E. C. Jerrrey for 
advice during the course of the work. 
This investigation was carried on in the Phanerogamic Labora- 
tories of Harvard University. 
А BIBLIOGRAPHY. 
1. Kraus, G., in Schimper's Traité de paléontologie végétale, Bd. 
V. pp. 363-385. 
2. GorHaN, W. Zur Anatomie lebender und fossiler Gymnosper- 
men-Hólzer. Abhandl. der kénigl. preussisch. geolog. Landesan- 
stalt. Neue Folge, Heft 44. Berlin, 1905. 
З. Ношалск, А. and Jerrrey, E. С. Affinities of certain Cretaceous 
Plant remains commonly referred to the genera Dammara and 
Brachyphyllum. American Naturalist, vol. XL. pp. 189-215. 
1906. 
4. HoLuickK, А. and Jerrrey, E. C. Studies of Cretaceous Coni- 
ferous remains from Kreischerville, New York. Memoirs of the 
New York Botanical Garden, vol. ITI. 1909. 
5. Jerrrey, E. C. Araucariopitys, a new genus of Araucarians. 
Botanical Gazette, vol. XLIV., pp. 435-444, 1907. 
6. GorHAN, W. Die fossilen Hölzer von König Karls Land. 
Kungl. Svenska. Vetenskapsakademiens Handlingar, Bd. XLII. 
No. 10, 1907. 
7. Gerry, Miss E. The distribution of the bars of Sanio in the 
Conifers. Annals of Botany (ined.) 
8. JErrnEY, E. C. and Curysiter, M. A. On Cretaceous Pity- 
i oxyla. Botanical Gazette, vol. XLII, pp.1-15, 1906. 
