. A textbook of botany for colleges and universities ... Botany. 142 MORPHOLOGY with Lycopodiales are (i) the vascular anatomy; (2) the soh'tary sporan- gium on the adaxial surface of the sporophyll; (3) the development of the sporangium from a transverse row of initial cells; (4) the trabeculae, which also^ appear in certain fossil Lycopodiales; (5) the ligule, which is present in all Lycopodiales except Lycopodium and Phylloglossum; and (6) the gametophytes, which resemble closely ' those of Selaginella. The characters not in common \\'ith Lycopodiales are (1) the large multiciliate sperms;
. A textbook of botany for colleges and universities ... Botany. 142 MORPHOLOGY with Lycopodiales are (i) the vascular anatomy; (2) the soh'tary sporan- gium on the adaxial surface of the sporophyll; (3) the development of the sporangium from a transverse row of initial cells; (4) the trabeculae, which also^ appear in certain fossil Lycopodiales; (5) the ligule, which is present in all Lycopodiales except Lycopodium and Phylloglossum; and (6) the gametophytes, which resemble closely ' those of Selaginella. The characters not in common \\'ith Lycopodiales are (1) the large multiciliate sperms; (2) the absence of a suspensor; (3) the general habit; and - (4) the highly specialized leaves.; (2) PSILOTALES This group of pteridophytes comprises two very small living genera: Psilolum (fig. 330), with two species occurring in the tropics of both hemispheres; and Tmesipteris (fig. 325), with a single Australasian species (sometimes more species are recognized). These forms are intro- duced here, not to present their life histories, but to illustrate very briefly cer- tain stages in the evolution of pteridophytes. Throughout Lycopo- diales there appears a tendency to increase the output of spores produced pjQ ^^^ _ Tmesip- by the sporophyte. The fcrw .• section of sporangia. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Coulter, John Merle, 1851-1928; Barnes, Charles Reid, 1858-1910, joint author; Cowles, Henry Chandler, 1869- joint author. New York, Cincinnati [etc] American book company
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1910
