A EUROPEAN PETRIFACTION WITH FOLIAGE. 495 
Authorities quoted in the Teat. 
CARRUTHERS, W.—1870. * On Fossil Cycadean Stems from the Secondary 
Rocks of Britain." Trans. Linn. Soc. vol. xxvi. pp. 675-708, 
pls. 54-63. 
Scorr, D. H.—1909. Studies in Fossil Botany. Vol. ii.: Spermophyta. 
Ed. 2, pp. xiii, 355-676, text-figs. London. 
SEWARD, A. C.—1897. “On Cycadeoidea gigantea, a new Cycadean Stem 
from the Purbeck Beds of Portland." Quart. Journ. Geol. Soc. 
vol. liii. pp. 22-36, pls. 1-5, text-figs. 1-3. 
Sroves, M. ©.—1910. * Adventitious Budding and Branching in Cycas.” 
New Phytologist, vol. ix. pp. 235-241, text-figs. 8-14. 
—— 1915. Catalogue of the Mesozoie Plants in the British Museum 
(Natural History): The Cretaceous Flora, part 2, pp. xxxvi, 360, 
pls. 1-32, 112 text-figs. London. i 
—— 1917. “ Roots in Bennettites.” Ann. Bot. vol. xxxi. pp. 257-259, 
pl. 14. 
Srores, M. C., and R. V. WHEELER.—1918. * The Constitution of Coal.” 
Tuomas, H. H., and N. Bancrorr.—1913. “On the Cuticles of some recent 
and fossil Cycadean Fronds.” Trans. Linn. Soc. Lond. ser. 2, Bot., 
vol. viii. part 5, pp. 155-204, pls. 17-20, 32 text-figs. 
WiEkLAND, G. H.—1899. “A Study of some American Fossil Cycads.— 
Part II. The Leaf Structure of Cycadeotdea.” Amer. Journ. Sci. 
ser. 4, vol. vii. pp. 305-308, pl. 7. New Haven. 
—— 1906. “American Fossil Cycads.” Publ. Carnegie Inst. no. 34 
pp. 296, pls. 50. Washington. 
—— 1916. “American Fossil Cycads, vol. ii.: Taxonomy." Publ. Car- 
negie Inst. no. 34, ii. pp. vii, 277, pls. 58. Washington. 
1 
Explanation of the Abbreviations used in the Texl-figures. 
In text-figure | letters a to r refer only to series of slides. 
In text-figures 2 to 4:— 
b. Baud below vascular bundle. — pv. Protoxylem. 
c. Cuticle of epidermis. we. X me, 1), Upper epidermis of leaf 
d. Dividing cells of cork cambium. and adjacent leaf, 
e. Epidermal cells. MERdlo sheath: 
g. Ground-tissue. a. Xylem. 
h. Hypodermal cells. z. Zone of hairs attached to lower 
Le. Lower epidermis. “surface of leaf;  * 
ph. Phloem. 
