48 Oliver and Salisbury . — On the S true hire and 
Pad. The central portion of the lens (p. 20). 
Plinth. The free portion of the nucellus supporting the lagenostome (p. 16). 
Plinth jacket. The epidermis of the soft integument surrounding the plinth. 
Shoulder. A term applied to that part of a structure where it begins to curve inwards towards 
the apex. 
Sinus. The space between the free portion of the nucellus and the integumental lining or the 
gaps in a fimbriated micropyle. 
Tapetal septum. The septum separating the megaspore cavity from the apex of the nucellus. 
Tent pole , 1 A raised central portion of the apex of the pro th alius. 
X. Literature cited. 
Arber, E. A. N. : On Some New Species of Lagenostoma. Proc. Roy. Soc., B., vol. 7 6, 1905. 
Campbell, D. H. : Mosses and Ferns. New York, 1905. 
Coulter and Chamberlain : Morphology of Spermophytes. New York, 1901. 
Hiras£, S. : Etudes sur la fecondation, etc., du Ginkgo biloba. Journ. Coll. Sci. Japan, vol. xii. 
Land, W. J. G. : On Ephedra. Bot. Gaz., vol. xxxviii. 
Lang, W. H. : On the Gametophytes and Ovule of Stangeria. Ann. Bot., vol. xiv, 1900. 
Lawson, A. A. : The Gametophytes and Embryo of Sciadopitys verticillata. Ann. Bot., vol. xxiv, 
1910. 
Lotsy, J. P. : Contributions to the Life-history of Gnetnm . Ann. Jard. Bot. Buitenzorg, vol. xvi. 
Oliver, F. W. : On the Ovules of the Older Gymnosperms. Ann. Bot., vol. xvii, 1903. 
: On Stephanospermum . Trans. Linn. Soc., 2nd ser., Bot., vol. vi, 1904. 
: Notes on Trigonocarpus and Polylophospermum. New Phyt., vol. iii, 1904. 
: On Physostoma degans . Ann. Bot., vol. xxiii, 1909. 
Oliver and Scott : On Lagenostoma Lomaxii, Phil. Trans. B., vol. cxcvii. 
Renault, B. : Cours de Bot. fossile, vol. iv. 
Salisbury, E. J. : On the Extrafloral Nectaries of the Genus Polygonum. Ann. Bot., vol. xxiii, 1909. 
Scott, D. H. : Studies in Fossil Botany, 2nd Ed., 1909. 
Stopes, M. C. : Beitrage zur Kenntnis der F ortpflanzungsorgane der Cycadeen. Flora, 1904. 
Williamson, W. C. : On the Organization of the Fossil Plants of the Coal Measures, Pt. viii. 
Phil. Trans., 1877. 
xi. explanation of plates 1 -11 1. 
Illustrating Messrs. Oliver and Salisbury’s paper on Conostoma group of Palaeozoic Seeds. 
U. C. L., R., and Q. — University College London Collection. 
J. = Dr. Jongmans* Collection. 
W. = Mr. D. M. S. Watson’s Collection. 
PLATE I. 
Figs, i-ii (Photographs). 
Fig. 1. Nearly longitudinal section through seed, showing the boat-shaped outline. The 
cushion (Is.) is in position just beneath the lagenostome (lg.), and the micropylar membrane (m.m.) 
has contracted from the hard testa (t.). U. C. L., R. 111 (Shore), x 1 2 (see p. 10). 
1 S. Hiras£ : Etudes sur la fecondation, etc., du Ginkgo biloba. Journ. Coll. Sci. Japan, vol. xii, 
p. 113- 
