. Un manuel de botanique cryptogamique. Les cryptogames. ii8 des cryptogames, Sigillariostrobm la fructification de Sigillaria, est extrêmement rare. C'était un cône ressemblant à Lepidostrobus, avec les sporanges placés individuellement sur la base de l'sporophylles. Les sporophylles sont largement lancéolées et apiculé. Seulement un type de spore a été découvert à l'heure actuelle, les mégaspores, mais il peut être considéré comme certain qu'ils ont été associés à une seconde et plus petit genre. Les fossiles connus sous le nom de Stigmaria sont les racines de Sigillaria, les deux ayant été trouvés pas rare dans le cadre d'un anothe

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. A handbook of cryptogamic botany. Cryptogams. ii8 VASCULAR CRYPTOGAMS Sigillariostrobm, the fructification of Sigillaria, is extremely rare. It was a cone resembling Lepidostrobus, with the sporanges placed singly on the base of the sporophylls. The sporophylls are broadly lanceolate and apiculate. Only one kind of spore has at present been discovered, the megaspores, but it may be regarded as certain that these were asso- ciated with a second and smaller kind. The fossils known as Stigmaria are the roots of Sigillaria, the two having been not unfrequently found in connection with one another. They occur in the Devonian and Carboniferous formations. Fragments have been found from twenty to thirty feet or more in length (S. ficoides, Brongn.), cylindrical arid unbranched, or the branching always dichoto- mous, the two branches running in a nearly parallel direction. The surface is smooth, with numerous shallow saucer-like depressions, the scars of the rootlets, some of which are still very commonly found attached to the primary root. The Stigmarije obviously lengthened. Fig. (yi.—Stigmaria jicoides Erongn. with rootlets. (After Solms-Laubach.) exclusively by apical growth. Transverse section shows a hollow ' vascular' cylinder, broken by meshes for the passage of the bundles of the rootlets, and consisting of scalariform tracheides with a central parenchyipatous tissue or ' medulla.' In the rootlets the single central bundle consists of a few scalariform tracheides, which leave the cylinder as a triangular bundle, but become circular in the rootlets. Under the term Lycopodites are included a number of fossil forms, the fructification of which is either entirely unknown, or is not in a suf- ficiently well-preserved state for definite determination. Some of the leafy stems ought possibly to be referred to Coniferse; others, with leaves of one kind only, perhaps belong to Lycopodiaceae ; while others, with leaves of two different kinds, are Selaginellacese. From bed

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