. Annual report of the Board of Regents of the Smithsonian Institution. Smithsonian Institution; Smithsonian Institution. Archives; Discoveries in science. PRESENT POSITION OF PALEOZOIC BOTANY—SCOTT. 395 erse the inner layers of the integument. The upper free part of the Jatter has a complex chambered structure; tliere are usually nine Chambers, each of which receives one of the integumental bundles, llie outer layer of the integument has a columnar structure The free apex of the nucellus is prolonged upward through the micropyle protruding somewhat beyond it, as an open tube. (Fi<r. 10 ) A
. Annual report of the Board of Regents of the Smithsonian Institution. Smithsonian Institution; Smithsonian Institution. Archives; Discoveries in science. PRESENT POSITION OF PALEOZOIC BOTANY—SCOTT. 395 erse the inner layers of the integument. The upper free part of the Jatter has a complex chambered structure; tliere are usually nine Chambers, each of which receives one of the integumental bundles, llie outer layer of the integument has a columnar structure The free apex of the nucellus is prolonged upward through the micropyle protruding somewhat beyond it, as an open tube. (Fi<r. 10 ) As in recent Cycads and in Ginkgo, the apex of the nucellus contains the polJen chamber, which here has a peculiar form, for the middle of the chamber is occupied by a solid column of tissue, reducing the actual cavity to an annular channel in which the pollen grains are found (See pi. I and fig. 10.) Within the body of the nucellus is the mem- brane of the megaspore or embryo sac. The seed was thus of com-. \^.—j^agenoBtoma homawi. Apox of seed in modian longitudinal soction through ot, outer part of testa ; r, palisade layer; ii, inner part of testa ; h, eavity between testa and nucellus; o, orifice of pollen-chamber, pc; cc. central column; vl. pollen-grams ; pi, nucellus ; mg, megaspore. x about 50. After Oliver. plex organization and shows that Lyginodendron, in spite of its sur- viving Fern-like characters, had definitely attained the rank of a typical Spermophyte. The structure of the pedicel indicates that the seed was borne on a foliar organ. The evidence of other species leaves no doubt that the sporophylls were modified fronds or pinnje of compound form, chiefly differing from the sterile foliage in the suppression of the lamina) of the leaflets. • The stellate lobed indusia or cupulos belonging to Cahjmmatotheca Strangeri, a species closely allied to Sphenoptens Ildninghaum, is shown in fig. 11, drawn 's original specimen.' Another rel
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