. Morphology of spermatophytes. [Part I. Gymnosperms]. Gymnosperms; Plant morphology. 148 MORPHOLOGY OF SPERMATOPIIYTKS. We have described the strohihis of Cycndeoidea Dacotensis as consist- ing (if a slieath of ovei-hipping Lracts, within which niicrosporophylls liear- ing Marattialike synangia occur. Witliiu the niicrosporophylls, and towards the hase id' the strohilus, there is discovered what at first sigiit apjieai's to he merely the conic- al apex (>i tlie axis of the strohilus, l)Ut whi(di proves to he the ovulate region (Fig. 104). The conical re- FiG 10^ —C t/caihotdea JJacoUn.^i^^
. Morphology of spermatophytes. [Part I. Gymnosperms]. Gymnosperms; Plant morphology. 148 MORPHOLOGY OF SPERMATOPIIYTKS. We have described the strohihis of Cycndeoidea Dacotensis as consist- ing (if a slieath of ovei-hipping Lracts, within which niicrosporophylls liear- ing Marattialike synangia occur. Witliiu the niicrosporophylls, and towards the hase id' the strohilus, there is discovered what at first sigiit apjieai's to he merely the conic- al apex (>i tlie axis of the strohilus, l)Ut whi(di proves to he the ovulate region (Fig. 104). The conical re- FiG 10^ —C t/caihotdea JJacoUn.^i^^ a very wmall part of a sonic- . i m • i i ; tangential longitudinal ceptacle IS covered all over with tlK scftiijn of a .'^trobilus, to show in side view the septa of a s}n- anLnuin, x S. — From prepara- tion made by (r. E. Wielanh from speeimen lu Yale Uni\'er- sitv Museum. characteristic stalked seeds and " in- terseiiiinal ; In this case the " receptacle "' really resembles an axis, and is of the ordinary Gymno- sperm type; while in BrniteUitcs and certain species of Cijcadeoidea the receptacle is flattened. This elongated ovulate axis is not always associated with a hi- sporangiate strohilus, as it occurs in strictly ovulate strobili. In Fig. 105 there is shown a transverse section (if a young ovulate stroliilus of Cycadeoidea colossaI- is, wdiose axis is of the elongated type, as in the hisporangiate C. Darohnsis (Fig. 101), l)ut wliicli is invested directly by the ensheathing ster- ile bracts. The illus- tratidu alsd sIkiws some of the cliaracter- istic ramenta which were packed between the siqierhcial sheath and the oviilifi'r(.ius. 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; Chamberlain, Charles Joseph, b. 1863. New York,
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