. Our native ferns and their allies : with synoptical descriptions of the American Pteridophyta north of Mexico. Ferns. And Their Allies 27 50. Lomaria (Fig. 7) stands inter- mediate between those genera in which there is an indusium formed of the revo- lute margin of the frond and those in which the indusium is remote from the margin. Our single species has dimor- phous fronds, free veins and the fructifi- cation in a broad band next the midvein, covered by a continuous and distinctly Bg. 7. Lomaria spicant, intramargiual indusium. This genus Desv. Eniargedsectionofthe ^j^^^j resembles the ne
. Our native ferns and their allies : with synoptical descriptions of the American Pteridophyta north of Mexico. Ferns. And Their Allies 27 50. Lomaria (Fig. 7) stands inter- mediate between those genera in which there is an indusium formed of the revo- lute margin of the frond and those in which the indusium is remote from the margin. Our single species has dimor- phous fronds, free veins and the fructifi- cation in a broad band next the midvein, covered by a continuous and distinctly Bg. 7. Lomaria spicant, intramargiual indusium. This genus Desv. Eniargedsectionofthe ^j^^^j resembles the next in general coirtracted fertile pinna snow- - . - . ing intramarginai indusium. ^abit and IS sometimes United with it. (Original.) 51. Blechnum.—In this genus the sori are linear and near the midvein, and are covered by a membranous indusium which is fixed at its outer margin, bursting at its inner margin when the sporangia are mature. A single representative is found within our limits. 52. ^Voodwardia.—Three species of chain-ferns occur within our limits, and each represents a distinct section based on the methods of venation. All have oblong or linear sori more or less sunken in the frond, covered by special lid-like indusia bursting at their inner margins, and arranged in chain-like rows near the midvein thus giving the popular name to the genus. EuwooDWARDiA has uniform fronds and veins forming at least one series of areolae between the sori and the margin. Anchistea has also uniform fronds but with free veins from the sori to the margin, while Lorinseria has dimorphous fronds and the veins everywhere uniting to form areolae, as in the sensi- tive-fern {Onoclea sensibilis). 53. Asplenium.—The numerous species of spleen worts are closely related to each other in their methods of fructification but differ widely in the form, texture and cutting of their fronds. The sori are placed on the upper side of an oblique vein (sometimes crossing it in Athyrium) and covered by
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Keywords: ., bookauthorunderwoo, bookcentury1800, bookdecade1880, bookyear1881
