506 Agnes Arber.—On the Structure of the Palaeozoic Seed 
The particular seed with which we have been concerned in this paper, 
Mitrospermum compressnm, is always found unattached, and the question of 
its attribution must be left open until further evidence is forthcoming. 
References. 
Andrews, E. B. (’75) : Description of Fossil Plants from the Lower Carboniferous Strata. Geol. 
Survey of Ohio, vol. ii : Geol. and Palaeontol., pt. ii : Palaeontology, 1875. 
Arber, Agnes (’10) : A Note on Cardiocarpon compression , Will. Proc Camb. Phil. Soc., vol. xv, 
Pt- D p. 393, 1910. 
Bertrand, C. E. (’07 ‘) : Les caracteristiques du genre Taxospermum de Brongniart. Bull, de la 
Soc. Bot. de France, t. liv, p. 213, 1907. 
--(’07 2 ) : Les caracteristiques du genre Diplotcsta de Brongniart. Ibid., t. liv, 
p. 389, 1907. 
-- (’07 3 ) : Les caracteristiques du genre Leptocaryon de Brongniart. Ibid , t. liv, 
p. 452, 1907. 
* --— (’07 4 ) : Les caracteristiques du genre Rhabdocarpus d’apres les preparations de la 
collection B. Renault. Ibid., t. liv, p. 654, 1907. 
--(’08 x ) : Les caracteristiques du Cycadinocarpus augustodunensis de B. Renault. 
Ibid., t. lv, p. 326, 1908. 
•— -(’08 2 ) : Les caracteristiques du genre Cardiocarpus d’apres les graines silicifiees 
etudiees par Ad. Brongniart et B. Renault. Ibid., t. lv, p. 391, 190S. 
-(’08 s ): La specification des Cardiocarpus de la collection B. Renault. Ibid., 
t. lv, p. 454, 1908. 
Brongniart, A. (’23) : Prodrome d’une histoire des vegetaux fossiles. Paris, 1S28. 
-(’74) : Etudes sur les graines fossiles trouvees a l’etat silicifie dans le terrain 
houiller de Saint-Etienne. Ann. Sci. Nat., Bot., t. xx, p. 234, 1874. 
-(’81): Recherches sur les graines fossiles silicifiees. Paris, 1881. 
Carruthers, W. (’72) : Notes on some Fossil Plants. Geol. Mag., Dec. 1, vol. ix, p. 1, 1872. 
Dawson, J. W. (’71): The Fossil Plants of the Devonian and Upper Silurian Formations of 
Canada. Geol. Survey of Canada, 1871. 
• - (’91) : On New Plants from the Erian and Carboniferous, and on the Characters 
and Affinities of Palaeozoic Gymnosperms. Canadian Record of Science, vol. iv (1890- 
1891), 1891. 
Grand’Eury, F. C. (’77) : Memoire sur la flore carbonifere du Departement de la Loire. Memoires 
de l’Academie des Sciences, t. lxxxiv, Paris, 1877. 
--(’05 x ) : Sur les graines trouvees attaches au Pecopteris Pluckeneti , Schlot. 
Comptes Rendus, t. cxl, p. 920, 1905. 
-(’05 2 ): Sur les Rhabdocarpus , les graines et revolution des Corda'itdes. 
Comptes Rendus, t. cxl, p. 995. 
Kidston, R. (’86) : Notes on some Fossil Plants collected by Mr. R. Dunlop, Airdrie, from the 
Lanarkshire Coalfield. Trans. Geol. Soc. Glasgow, vol. viii, p. 47, j886. 
-(’94) : On some New Species of Fossil Plants from the Lower Carboniferous Rocks of 
Scotland. Proc. Roy. Phys. Soc. Edinburgh, vol. xii, 1894. 
Lindley, J., and Hutton, W. (’31) : The Fossil Flora of Great Britain, vol. i, London, 1831-3. 
Newberry, J. S. (’73) : Descriptions of Fossil Plants from the Coal Measures of Ohio. Geol. 
Survey of Ohio, vol. i: Geol. and Palaeontology, pt. ii: Palaeontology, 1873. 
Oliver, F.W. (’03): The Ovules of the Older Gymnosperms. Annals of Bot., vol. xvii, p. 451,1903. 
--( 04) : On the Structure and Affinities of Stephanospermum ; Brongn. Trans. Linn. 
Soc. Lond., Botany, vol. vi, ser. 2, p. 361, 1904. 
