The microscope and its revelations . ight of a bud or gemmaof the simplest possible kind, and one of the first acts ofwhich is to put-forth other buds, whereby the rapid extensionof these plants is secured, although no separate individualever attains more than a very limited size. 218. In the Ferns we have in many respects a near approxi-mation to Plowering-plants ; but this approximation does notextend to their Reproductive apparatus, which is formed upona type essentially the same as that of Mosses, but is evolved at a very different periodof life. As the componenttissues of which theirfabri
The microscope and its revelations . ight of a bud or gemmaof the simplest possible kind, and one of the first acts ofwhich is to put-forth other buds, whereby the rapid extensionof these plants is secured, although no separate individualever attains more than a very limited size. 218. In the Ferns we have in many respects a near approxi-mation to Plowering-plants ; but this approximation does notextend to their Reproductive apparatus, which is formed upona type essentially the same as that of Mosses, but is evolved at a very different periodof life. As the componenttissues of which theirfabrics are composed, areessentially the same asthose which wiU be de-scribed in the next chapter,it wiU not be requisite hereto dwell upon them. Thestem (where it exists) isfor the most part made-up of cellular parenchyma,which is separated into acortical and amedullary por-tion, by the interposition ofa circular series of fibro-vascular bundles contain-ing true woody tissue andducts. These bundles forma kiad of irregular net- FiG. ObUtlue section of footstalk oZ Fern-leaf,showing bundle of sealariform ducts. FRUCTIFICATION OF FEENS. 399 Fig. 141. I work, from which prolongations are given-off that pass intothe leaf-stalks, and thence into the mid-rib and its lateralbranches; and it is their peculiararrangement in the leaf-stalks, whichgives to the transverse section ofthese the figured marking com-monly known as King Charlesin the oak. A thin section, espe-cially if somewhat oblique (Fig. 140),displays extremely well the peculiarcharacter of the ducts of the Pern;which are termed scalariform, fromthe resemblance of the regular mark-ings on their walls to the rungs of aladder.—What is usually consideredthe fructification of the Perns,affords a most beautiful and readily-prepared class of opaque objects forthe lowest powers of the Microscope;nothing more being necessary, thanto lay a fragment of the frond thatbears it on its under surfacQ, uponthe glass stage-plate, or to ho
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