. A handbook of cryptogamic botany. Cryptogams. LYCOPODJACE^ 63 and apiculate, and are penetrated by a single ' vascular ' bundle ; those which subtend the sporanges are much smaller, and apparently deeply bifid, in consequence of their becoming connate at their base in pairs. In Psilotum the leaves are reduced to mere scales without any 'vascular' bundle. The sporanges of the Psilotese differ from those of the Lycopodiese in not being formed in connection with the leaves, and in being pluri- locular. They are collected into spikes which are formed at the growing point of a primary shoot. In T
. A handbook of cryptogamic botany. Cryptogams. LYCOPODJACE^ 63 and apiculate, and are penetrated by a single ' vascular ' bundle ; those which subtend the sporanges are much smaller, and apparently deeply bifid, in consequence of their becoming connate at their base in pairs. In Psilotum the leaves are reduced to mere scales without any 'vascular' bundle. The sporanges of the Psilotese differ from those of the Lycopodiese in not being formed in connection with the leaves, and in being pluri- locular. They are collected into spikes which are formed at the growing point of a primary shoot. In Tmesipteris each spike usually consists of two sporanges only, situated in the fork be- tween two connate or one bifid fertile leaf; they are oblong and bilocular, and dehisce by two vertical slits ; the spores are very minute, oblong, and curved. In Psilotum the sporanges are col- lected into groups of three or four on special shott lateral branches, each in the axil of a rudimentary leaf, and forming a loose spike. They are turbinate in form, and are divided into three compart- ments, less often into two or four ; each locule dehisces by a vertical fissure. The germination of the spores and the oophyte generation are entirely unknown in the order. Psilotum consists of two spe- cies, natives of the tropical regions of both hemispheres, having the appearance of small branching nearly leafless shrubs ; Tmesipteris of a single known species, epiphytic on the trunks of tree-ferns, with a pendulous habit, in the Southern Fig. 41.—Tmesipteris tannensis Bernh. A, por-^ tion of branch (natural size); B, sporange and subtending leaves (magnified). Literature. Spring—Monograph des Lycopodiacees in M^m. Acad 1849. Cramer—(L. Selago) in Nageli u. Cramer's Pflanzenphys. De Bary—(Germination) Naturf. Gesell. Freiburg, 1858. Mettenius—(Phylloglossum) Bot. Zeit., 1867, p. 97. Payer—Botanique Cryptogamique, 1868. Juranyi—(Psilotum) Bot. Zeit., 1871, p. 177. Hegelmaier
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