. Fossil plants : for students of botany and geology . Paleobotany. 120 CONIFBEALES (EBCENT) [CH. in Sciadopitys 7—9. Fig. 686, E represents half a cone of Taxodium in which the distally expanded woody ends of the scales are tightly joined by their edges and form a hard case enclosing as in an ovary several angular seeds, the slender stalks being shrivelled and inconspicuous. The cones of the Cupressineae and CaUi- trineae are characterised by a whorled arrangement and a com- paratively small number of the scales. In Cupressus the cones are oval or spherical and each scale "bears 6—20 see
. Fossil plants : for students of botany and geology . Paleobotany. 120 CONIFBEALES (EBCENT) [CH. in Sciadopitys 7—9. Fig. 686, E represents half a cone of Taxodium in which the distally expanded woody ends of the scales are tightly joined by their edges and form a hard case enclosing as in an ovary several angular seeds, the slender stalks being shrivelled and inconspicuous. The cones of the Cupressineae and CaUi- trineae are characterised by a whorled arrangement and a com- paratively small number of the scales. In Cupressus the cones are oval or spherical and each scale "bears 6—20 seeds: in the Callitrineae the cones are valvular (figs. 703, 762, B—^D) and the scales vary from 2 to 3 in Callitris and from 7 to 8 in Widdringionia. The small cones of Saxegothaea consist of one-seeded mega- sporophylls which become fleshy and par- tially concrescent (fig. 687); in Juniperus the strobilus has the appearance of a berry; in Microcachrys the leaves pass gradually into the single-seeded verticillate megaspo- rophylls, 'each with two vascular strands ^ (fig. 684, T) and an epimatium, a, on one side of the ovule; in the ripe cone the mega- sporophylls are fleshy but not connate as in Saxegothaea^. In Dacrydium the megaspo- rophylls difEer but slightly from the fohage leaves in some species, in D. Balansae (fig. 684, P) a single leaf at the apex of a branch bears an ovule partially covered by a hood-like epimatium. In Torreya^ a very short shoot in the axil of a leaf bears two bracts and each subtends an ovule and two pairs of bracteoles. The seeds of T. cali- fornica, which may be 4 cm. long, are enclosed by a thick integument differentiated into a sarcotesta and sclerotesta surrounding a ruminated endosperm (fig. 688): there is a ring of vascular bundles at the limit of the free part of the integument and this is regarded by Oliver* as homologous with the tracheal plate at the base of. FrG. 687. Saxegothaea con- spicua. (After Stiles.) ' WorsdeU (99). 2 S
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