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1.
Cunninghamiostrobus goedertii is described as a new species based on permineralized seed cones from the Early Oligocene of Washington. The fossils come from the Makah Formation and were found on the northern shore of the Olympic Peninsula. The cone consists of numerous bract-scale complexes arranged helically around a central axis. Each bract-scale complex has a large bract bearing a small flap of tissue adaxially that represents the ovuliferous scale. Up to three seeds were produced on each complex. The vascular trace to the bract-scale complex diverges from the vascular cylinder of the cone axis as a concentric strand. This divides in the outer cortex of the axis to form a large collateral bract tract abaxially and a minute scale trace adaxially. The latter continues outward to supply the ovuliferous scale. The bract trace divides, forming many strands outward which occur in a row with transfusion tissue between them. Many resin canals also occur in the bract. The new cone combines features found in modern cones of Athrolaxis, Cunninghamia, and Taiwania but is most similar to Cunninghamiostrobus yubariensis from the Late Cretaceous of Japan.  相似文献   

2.
Picea eichhornii n. sp. is described from anatomically preserved seed cones. The fossils are from the Early Oligocene Jansen Creek Member of the Makah Fm. which is exposed along the northern shore of the Olympic Peninsula, Washington. The cones are at least 5.5 cm long and up to 3.5 cm in diameter. The cone axis is 4–6 mm in diameter and contains a pith made up of thick-walled parenchyma cells. Resin canals occur in a single ring in the secondary xylem in some specimens but are absent in others. The cortex is mostly parenchymatous and contains numerous large axial resin canals that branch to supply the bract and scale. Vascular traces to each scale and its subtending bract diverge separately from the vascular cylinder of the cone axis. The bract is tongue-shaped and keeled at its base. It is 5 mm wide and up to 9 mm long. The bract trace fades out before entering the bract base while two resin canals extend into the bract base. The ovuliferous scale is about 2.3 cm long and has a thin, probably papery, apex. Resin canals of the scale occur abaxial to the vascular tissue in the scale base, but some bend around the margins of the vascular strand to become adaxial outward. About 20 resin canals occur in the abaxial scale sclerenchyma, and this is the main anatomical feature that distinguishes these cones as a new species. There are less than 14 such canals in cones in a reference collection of 15 modern species and in the two fossil species known from anatomically preserved material. While the new species adds to our knowledge of the diversity of Cenozoic Picea, its affinities within the genus remain undetermined.  相似文献   

3.
Fossils from the Oligocene of western Montana described in this treatment are the first structurally preserved ovulate cones of Pinus to be reported from the Tertiary of North America. They are about 5.5 cm long and have a maximum diam of 2.5 cm. Numerous scales are arranged spirally around the axis and each scale bears two winged seeds. The bract subtending the ovuli-ferous scale is 3-4 mm long and is free from the scale throughout its length. The pith and cortex of the axis are constructed of thick-walled parenchyma cells and 18-21 resin canals occur at the inner edge of the cortex. Resin canals entering the base of the ovuliferous scale are restricted to the abaxial side with vascular tissues occupying the adaxial side. Vascular strands near the tip of the scale are strongly rounded on the adaxial or phloem side. At the abaxial side of the tip of the ovuliferous scale is a broadly rhomboidal apophysis with a raised umbo that terminates in a short spine. The fossils differ from the several Recent cones examined in having fewer resin canals and biseriate rays in the secondary xylem of the cone axis. The shape of the cone, its anatomical features, and the morphology of the tip of the cone scale indicate affinity with the subgenus Diploxylon.  相似文献   

4.
5.
A silicified seed cone of Oligocene age from the Olympic Peninsula of Washington represents a new species of Pinus. The cone was about 8 cm long and 3 cm at its widest diameter in the living condition. Its scale apices are thickened and each has a dorsal umbo. Internal cone construction confirms the assignment of the new species to Pinus and suggests affinity with the subsections Australes and Ponderosae of the section Pinus, subgenus Pinus. The cone is peculiar in having a stout bract trace that is slightly concave on its adaxial side and in having resin canals that diverge from the axial secretory system toward the bract but constrict markedly and terminate before entering the bract.  相似文献   

6.
Pinus mutoi is described as a new species on the basis of a permineralized seed cone from the Upper Cretaceous of Hokkaido, Japan. The cone is at least 20 cm long and up to 6 cm in diameter, consisting of a cone axis and numerous cone-scale complexes that are arranged helically around the axis. Two winged seeds are borne on the adaxial surface of each ovuliferous scale. Each complex receives a single trace from the vascular cylinder of the cone axis. In the scale base, all the resin canals occur abaxially to the vascular strand. The spatulate bract of the fossil is unique to the specimen among the cones of both living and fossil Pinus. The central umbo, broad sclerotic cortex of cone axis, and absence of serotinous features of the fossil cone suggest affinity with the subsection Sylvestres of the section Pinus, subgenus Pinus. This is the first record of permineralized preserved Pinus cone from the Cretaceous of Eastern Eurasia.  相似文献   

7.
Nephrostrobus cliffwoodensis gen. et sp. nov., Nephrostrobus bifurcatus sp. nov., and Rhombostrobus cliffwoodensis gen. et sp. nov. are described based on anatomical studies of seed cone fragments from the Upper Cretaceous Magothy Formation of New Jersey. These species belong to the Taxodiaceae. As in Sequoia, Sequoiadendron. and Metasequoia, the vascular strands supplying the scale and bract in Nephrostrobus are about equal. These vascular strands are arranged in a reniform pattern resembling that found in Metasequoia, but the orientation differs by 180 degress. Nephrostrobus cliffwoodensis and Nephrostrobus bifurcatus differ from each other in the branching of the complex trace and associated resin canals. Rhombostrobus cliffwoodensis resembles Cunninghamia in the arrangement of vascular strands and associated resin canals in its bract-scale complexes. However, the relative amount of bract and ovuliferous scale making up the complex is more like that in Sequoia. This combination of cone features does not occur in any of the extant genera. Nephrostrobus and Rhombostrobus are not considered to be ancestral to any of the extant taxodiaceous genera, but are extinct members of an ancestral complex from which the extant genera were derived.  相似文献   

8.
A silicified cone from the Late Eocene of Washington is described as a new fossil species of Pinus. The cone was probably 9–10 cm long and 3–5 cm at its widest diam in the living condition and is peculiar in having abundant resin canals in the secondary xylem of the axis arranged in three concentric rings near the cone base. The bract of the fossil is also unusual in having resin canals of distinctly unequal sizes and a vascular strand that is adaxially concave. In the absence of external features of the scale tips, these anatomical conditions along with the construction of the outer cortex of the axis of thick-walled cells suggest closest affinity of the new species with the subsections Contortae, Oocarpae, and Sylvestres of the section Pinus, subgenus Pinus.  相似文献   

9.
A sciadopityaceous seed cone, Sciadopityostrobus kerae, gen. et sp. nov., is described on the basis of a permineralized specimen from the Upper Cretaceous (Cenomanian–Coniacian) of Hokkaido, Japan. The peel method was applied for anatomical observations. The seed cone consists of a cone axis receiving numerous cone scale complexes that are arranged helically. Each complex generally has five inverted ovules that are oriented adaxially. The cone is similar to those of living Sciadopitys verticillata with respect to its peltate cone scale complex, with free apices of both bract and ovuliferous scale, trichomes on the bract, and a trifurcated ovuliferous scale strand. In the fossil, the bract and ovuliferous scale strands fuse with each other in the basal part of the cone scale complex, while S. verticillata bract and ovuliferous scale strands are derived separately from the vascular cylinder and remain separate throughout their length. The present specimen is one of the oldest records of structurally preserved cones that can be assigned to the family Sciadopityaceae.  相似文献   

10.
11.
Silicified leaves, dwarf shoots, pollen cones, and seed cones of Pinus from a Late Miocene chert bed within the Yakima Basalt Formation near Yakima, Washington are interpreted as coming from a single new species, P. foisyi. The needles and dwarf shoots are those of a three-needle pine. The needles contain two to four medial resin canals, a biform hypodermis, and endodermal cells with uniformly thickened walls. The pollen cones are ellipsoidal and about 1 cm long, and many contain bisaccate pollen grains. The seed cones are at least 6 cm long and are slightly asymmetrical. The cone axis has a broad sclerotic outer cortex, and the seed wing extends from a thick parenchymatous base. The scale apex bears a conspicuously swollen projection. The foliage and seed cones are identifiable with the Subgenus Pinus, Section Pinus, Subsection Oocarpae independently of one another, and together indicate a fossil species related to the modem Californian closed cone pines. Pinus foisyi represents one of the earliest occurrences of cone asymmetry associated with this group. However, cone serotiny characteristic of the modem species appears to have evolved after the Late Miocene.  相似文献   

12.
Yubaristrobus is a new genus of the Taxodiaceae based on a permineralized seed cone from the Upper Cretaceous of Hokkaido. The type species,Y. nakajimae sp. nov., is characterized by peltate bract-scale complexes consisting of a completely-fused bract and scale. The bract-scale complexes are spirally arranged as in most taxodiaceous genera. Their vascular arrangement is specialized and unique in the Taxodiaceae and suggests a relationship with the Cupressaceae. Consecutive number from the previous paper (Ohsawa, M. Nishida and H. Nishida, 1992b).  相似文献   

13.
Ovulate cones identified as Abietites ellipticus Fontaine, from the Early Cretaceous of northern California, have been reinvestigated. Rather than being preserved as imprints as originally described, the fossils are petrified. Two cones are attached to needle-bearing twigs. The organs are similar to those of the living Cunninghamia lanceolata. However, the scale portion of the bract-scale complex of the fossil cones is situated close to the bract apex, while that in modern Cunninghamia cones is midway between the bract base and apex. This plus other structural differences warrant treatment of the material as a new species of Cunninghamiostrobus Stopes and Fujii.  相似文献   

14.
Seed cones in Taxodium distichum and Glyptostrobus pensilis occupy the position of permanent shoots and are initiated in the summer preceding spring pollination. Morphological features are similar in the two genera, reflecting their close taxonomic relationship. Ovule complexes originate as two (rarely more) ovule primordia in the axil of each fertile bract but without any indication of a preceding discrete ovuliferous scale. When the nucellus, integument, and micropyle are well developed, a series of up to ll abaxial lobes forms at the base of each ovule pair. They become fused by basal growth. After pollination the common basal meristem of lobes and bract extends by intercalary growth to form the conspicuous “ovuliferous scale” of the mature cone; the lobes enlarge and exceed the ovules. Despite the topographic similarity in the cones of both genera, there are differences in vasculature such that the vascular traces to the axillary complex originate directly from the axial cylinder in Glyptostrobus but from the bract trace in Taxodium. The complex vasculature of the mature cone develops late and primarily as an expression of intercalary growth.  相似文献   

15.
Fossils described in this treatment are the first structurally-preserved ovulate cones of Picea to be reported from the Tertiary. They are 5.0-5.8 cm long and 1.6-1.8 cm at their widest diameter. Numerous ovuliferous scales are arranged spirally around the axis and each bore two winged seeds. The bract subtending the scale is 4.0-7.0 mm long and is fused to the scale for 1.0 mm. The base of the bract is inflated on the abaxial side extending for about 1.0 mm between the seeds of the adjacent scales. Both the scales and their subtending bracts are recurved at their point of divergence from the axis. The ovuliferous scales taper gradually to a point, and the thickness of the tissues at the scale apex indicates that they were woody. Anatomically, the silicified cones are very similar to those of the Recent species and indicate that all important features of the latter had evolved by Oligocene time.  相似文献   

16.
Comparisons are presented between the three-dimensional airflow patterns created around and by a scale model of a conifer ovulate cone and the trajectories of windborne pollen grains around Picea, Larix, and Pinus ovulate cones. Three general components of the airflow pattern around an ovulate cone model are 1) doldrum-like eddies, rotating over the adaxial surfaces of cone scales and directed toward attached ovules, 2) airflow spiralling around the cone axis along cone scale orthostichies and parastichies, and 3) a complex pattern of vortices (“umbilicus”) directed toward the leeward surface of the ovulate cone. The observed trajectories of pollen grains around cones of Picea, Larix, and Pinus conform to two of these three airflow components: 1) pollen grains are seen to roll along cone scales toward the distal scale margin and to become reentrained in airflow directed backward toward attached ovules, and 2) pollen grains passing around the cone are deflected into the “umbilicus” airflow pattern, where they either settle on or impact with cone scales (approach trajectories), or where they approach the leeward cone surface but are deflected away by airflow passing under the cone (Z-shaped trajectories). Vectoral analyses of pollen grain motion reveal a complex pattern of trajectories influenced by boundary layer conditions defined by ovulate cone geometry and ambient airflow speed. Wind tunnel studies of ovulate cones subtended by leaves and stem indicate that leaves circumscribing the cone act as a snowfence, deflecting windborne pollen toward the cone. Vectoral analyses of airflow patterns and pollen grain trajectories close to ovulate cones indicate that wind pollination in conifers is a non-stochastic aerodynamic process influenced by cone-leaf morphology and the behavior of pollen grains as windborne particles.  相似文献   

17.
18.
Several silicified ovulate cones from the late middle Miocene (Barstovian) represent a new species, Picea wolfei Crabtree. This is the second species of Picea for which structurally preserved seed cones are known to be reported from the Tertiary. The cones are 5.0–8.0 cm long and 1.5–2.0 cm at their greatest diameter. Ovuliferous scales are inserted helically around the cone axis and are recurved at their point of divergence. Each scale is broadly obovate to spatulate with a rounded apex and bore two seeds adaxially. The bract subtending the scale is 4.5–7.3 mm long and is fused to the scale for 1.4–2.0 mm. Each bract has an inflated keel-like base which projects abaxially between the seeds of adjacent scales. The fossil cones superficially resemble those of the extant Picea breweriana, yet differ from them anatomically. The new species also resembles Picea lahontense, a fossil compression from the Miocene Trout Creek Flora of south-central Oregon, but the different modes of preservation preclude meaningful comparison. Picea diettertiana, the only structurally preserved fossil cone of this genus previously described, is quite dissimilar in that it lacks a sclerotic pith.  相似文献   

19.
Archicupressus is a new genus of the Cupressaceae based on a permineralized conifer female cone from the Upper Cretaceous of Hokkaido. The type species,Archicupressus nihongii sp. nov., is characterized by peltate bract-scale complexes consisting of a completely fused bract and scale bearing erect seeds. Bract-scale complexes are arranged in whorls of three on the cone axis. Each complex has a bristle-like projection, the bract apex, at the top. Affinities to some genera in the Cupressaceae are discussed. Consecutive number from the previous paper (Ohsawaet al., 1992). Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan to Makoto Nishida, No. 02640533.  相似文献   

20.
Silicified rhizomes from Miocene strata near Yakima, Washington represent a new species of Osmunda. The stems are 8–13 mm in diameter and are surrounded by a thick sheath of adherent leaf bases, each of which shows stipular expansions typical of the Osmundaceae. The new species has an ectophloic siphonostele in which the xylem cylinder is dissected by leaf gaps with 12–14 strands being visible in a given stem cross section. Such sections also show 12–16 leaf traces in the cortex. The xylem of each leaf trace diverges from the xylem cylinder of the stem as an adaxially concave strand with its protoxylem organized into a single medial adaxial cluster. Initial bifurcation of the leaf-trace protexylem occurs as the leaf trace passes through the outer cortex of the stem. In the basal part of the stipular region of the petiole base, thick-walled fibers form an arch on the abaxial side of the sclerenchyma ring around the petiolar bundle. This arch persists throughout most of the length of the stipular region, with the thick-walled fibers becoming reorganized into two lateral masses in the distal part of the stipular region. Similar thick-walled fibers form an elongate strip of tissue in each wing of the stipule along with several small clusters scattered near the sclerenchyma ring. The new species belongs to the subgenus Osmunda and shows that during the Neogene, the latter existed as a group of closely related species much as it does today. Furthermore, Osmunda wehrii combines features of the modern O. regalis, O. japonica, and O. lancea with those of O. claytoniana and thus supports the inclusion of the latter species in the subgenus Osmunda.  相似文献   

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