Probable Fertile Region of Asteroxylon mackiei K. and L.

Nature ◽  
1964 ◽  
Vol 203 (4949) ◽  
pp. 1082-1083 ◽  
Author(s):  
A. G. LYON
Keyword(s):  
Fertile Region

Studies of marine algae in the lesser-known families of the Gigartinales (Rhodophyta). III. The Mychodeaceae and Mychodeophyllaceae

1978 ◽  
Vol 26 (4) ◽  
pp. 515 ◽  
Author(s):  
GT Kraft
Keyword(s):  
Marine Algae ◽  
Adjacent Cell ◽  
Distinctive Pattern ◽  
Supporting Cells ◽  
New Family ◽  
Red Algal ◽  
Single Genus ◽  
Fusion Cell ◽  
Fertile Region ◽  
Axial Development

The endemic Australian red algal families Mychodeaceae Kylin and Mychodeophyllaceae fam. nov. are described and characterized in vegetative and reproductive detail. The Mychodeaceae is composed of the single genus Mychodea and 11 species which are distinguished on habit features and vegetative differences. Plants are uniaxial with a distinctive pattern of axial development, monoecious, zonately tetrasporangiate, procarpic and polycarpogonial. Supporting cells of carpogonial branches function as auxiliary cells which remain unfused to adjacent cells after diploidization and emit numerous gonimoblast filaments towards the centre of the thallus. The gonimoblasts become secondarily pitconnected to gametophytic cells which they lie next to and eventually appear to break up into isolated groups of cells which both initiate additional carposporangial precursors and enlarge directly into carposporangia themselves. Carposporangial initials can form secondary pit-connections to any type of adjacent cell, which results in irregularly branched carposporangial clusters whose cells are frequently attached to sterile gametophytic cells within and around the periphery of the cystocarp. Mature cystocarps consist of a non-ostiolate pericarp and pockets of carposporangia isolated between persistent sterile cells throughout the fertile region. The genera Neurophyllis Zanardini and Ectoclinium J. Agardh are placed in synonymy with Mychodea, and all extra-Australian records of the group are discounted or questioned. A new family, the Mychodeophyllaceae, is created for Mychodeophyllum papillitectum gen. et sp. nov. from Western Australia. Mychodeophyllum shares spermatangial and tetrasporangial features with Mychodea, as well as sexual elements such as polycarpogonial procarps, lack of a fusion cell, and multiple, inwardly growing gonimoblast initials. Gonimoblast filaments develop quite differently from Mychodea, however, and carposporangia form radiating chains around the periphery of a central placenta composed of mixed and secondarily connected gonimoblast and gametophytic filaments. Plants of the genus are also apparently rnultiaxial. The Mychodeaceae and Mychodeophyllaceae appear to be highly specialized in vegetative and carposporophyte structure, and have given rise to no known higher lines of development. It is speculated that both families may represent offshoots from ancestors at a level of carposporophyte complexit) represented by present-day Rhabdoniaceae, Solieriaceae and Rhodophyllidaceae.

The Mines and Miners of Ancient Athens

1961 ◽  
Vol 8 (2) ◽  
pp. 138-151 ◽  
Author(s):  
R. J. Hopper
Keyword(s):  
Industrial Area ◽  
Eastern Coast ◽  
The Road ◽  
Ancient Athens ◽  
Industrial Buildings ◽  
Olive Groves ◽  
The Hill ◽  
The Village ◽  
Fertile Region ◽  
Sea Coast

A Traveller from Athens who takes the inland route to Cape Sounion will pass from the plain of Athens, between Hymettos and Pentelikon, to enter the pleasant and fertile region of the Mesogia. Through the vineyards and olive groves, and through the attractive and populous villages of Paiania, Koropi, Markopoulo, and Keratea, the road bears on south-eastwards to encounter and cross a hill barrier close to the eastern coast of Attica. Descending by this road as it winds through the Plaka Pass to Thorikos and the sea the traveller is struck by the changing aspect of the country. Already in the Plaka Pass there is a hint of an abandoned industrial area such as is encountered in Derbyshire. The impression produced by these first indications of industry is strengthened after the descent to the level of the sea-coast. The charm of Attica's shore, so apparent elsewhere, is here destroyed by an ugly village with great dark mounds like those of a Yorkshire colliery or Scottish shale mine. There are also industrial buildings, for the most part derelict, looking not unlike enlarged Nonconformist chapels in the nineteenth-century tradition. Up the hill-side stretches a curious brick tunnel, with smoke stacks at intervals, intended to remove the noisome vapours generated in the processes here carried out. This is the village of Lavrion. Its other modern name of Ergasteri underlines its character. It is a profoundly depressing place, and one passes through it with relief to regain the road to Sounion.

X.—Some Specimens of Lyginorachis papilio Kidston Associated with Stems of Pitys

1963 ◽  
Vol 65 (10) ◽  
pp. 211-224 ◽  
Author(s):  
Albert G. Long
Keyword(s):  
Leaf Trace ◽  
Vascular Bundles ◽  
Fertile Region

SynopsisLyginorachis papilioKidston is shown to possess separate vascular bundles at its base like the leaf-trace inPitys dayiGordon. Vascular traces arise higher up indicating that the petiole bore one or two pairs of sub-opposite pinnæ (or pinnules). Above these the primary rachis dichotomizes into secondary rachides with traces to alternate pinnæ. One specimen is known showing the origin of an axis ofTristichia ovensiin the dichotomy.L. papiliois considered to be a petiole ofPitysandT. ovensithe fertile region of the frond bearingStamnostomacupules.

Metasequoia milleri n.sp., anatomically preserved pollen cones from the Middle Eocene (Allenby Formation) of British Columbia

1979 ◽  
Vol 57 (8) ◽  
pp. 958-970 ◽  
Author(s):  
Gar W. Rothwell ◽  
James F. Basinger
Keyword(s):  
British Columbia ◽  
Middle Eocene ◽  
Metasequoia Glyptostroboides ◽  
Plant Remains ◽  
Exine Ornamentation ◽  
Pollen Sacs ◽  
Pollen Cone ◽  
Fertile Region ◽  
A New Species ◽  
Subtending Leaves

The discovery of well preserved, permineralized plant remains in Eocene sediments near Princeton, British Columbia, provides an opportunity to describe Metasequoia milleri, a new species of taxodiaceous pollen cone. Individual specimens are up to 3.0 mm long and 2.9 mm in diameter and are subtended by a vegetative zone of scale-like leaves. Approximately 30 microsporophylls are attached to the axis, and each bears three ovoid pollen sacs. The distal-most subtending leaves imbricate and enclose the fertile region. Pollen is ovoid to subspheroidal with an erect, protruding leptoma. Grains measure 19–27 μn in diameter and have verrucate exine ornamentation with numerous orbicules. These fossils show that pollen cones anatomically similar to those of extant Metasequoia glyptostroboides were present as early as Middle Eocene time.

Vamsapriya yunnana, a new species of Vamsapriya (Xylariaceae, Xylariales) associated with bamboo from Yunnan, China

Phytotaxa ◽  
2018 ◽  
Vol 356 (1) ◽  
pp. 61 ◽  
Author(s):  
HONG-BO JIANG ◽  
RUNGTIWA PHOOKAMSAK ◽  
DARBHE JAYARAMA BHAT ◽  
SEHROON KHAN ◽  
ALI BAHKALI ◽  
...  
Keyword(s):  
New Species ◽  
Bayesian Inference ◽  
Maximum Likelihood ◽  
Dna Sequence ◽  
Yunnan Province ◽  
New Taxon ◽  
Apical Appendage ◽  
Fertile Region ◽  
A New Species

Vamsapriya yunnana sp. nov., collected from dead bamboo in Yunnan Province of China, is described and illustrated in this paper. The new taxon is characterized by synnematous conidiophores, with enteroblastic, monotretic conidiogenous cells and brown to dark brown, 4–9-septate, fusiform conidia with a long, apical, appendage-like region. The species differs from the type and other species in the genus in having a wider fertile region and rostrate apex of the conidia. Maximum likelihood and Bayesian inference analyses of a combined ITS, LSU and RPB2 DNA sequence dataset show that V. yunnana is a new species, belonging to the genus Vamsapriya in Xylariaceae.

Fine structure of conidiogenesis in the holoblastic, sympodial Tritirachium roseum

1973 ◽  
Vol 51 (11) ◽  
pp. 2033-2036 ◽  
Author(s):  
Terrence M. Hammill
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Fine Structure ◽  
Conidiogenous Cell ◽  
Full Size ◽  
Distal Half ◽  
Electron Transmission ◽  
Proximal Half ◽  
Conidiogenous Locus ◽  
Fertile Region

Electron microscopy of conidiogenesis in Tritirachium roseum was done on material fixed in glutaraldehyde followed by OsO4. The walls of conidiogenous cells, though pigmented, lacked well-defined differential electron-transmission layers. Conidial initials developed without the appearance of a rupture in the conidiogenous cell wall, i.e., development was holoblastic. Each successively produced conidiogenous locus developed below and to one side of the previously formed conidium, and the fertile region of the conidiogenous cell elongated in a geniculate pattern. After each conidial initial reached full size, it was delimited by a centripetally developing septum, which increased in thickness, became double, and split during conidial secession. The distal half of a split septum formed the conidial base; the proximal half remained as part of the conidiogenous cell wall. Upon conidial secession, basal frills on conidia, and secession scars on conidiogenous cells were especially conspicuous.

scholarly journals Impressed Ware blade production of Northern Dalmatia (Eastern Adriatic, Croatia) in the context of Neolithisation

2019 ◽  
Vol 46 ◽  
pp. 352-374
Author(s):  
Sonja Kačar
Keyword(s):  
Raw Material ◽  
Social Aspects ◽  
Early Neolithic ◽  
High Quality ◽  
Lithic Assemblages ◽  
The Social ◽  
Production Techniques ◽  
Material Economy ◽  
Fertile Region ◽  
Blade Production

The lithic assemblages from the principal early Neolithic sites in Northern Dalmatia have been analysed with respect to the technological aspects and principles of schéma and chaîne opératoire, débitage economy and raw material economy. Northern Dalmatia, the most fertile region of the Eastern Adriatic, hosts the most important Neolithic open-air sites. Early Neolithic is associated with the Impressed Ware culture and dates back to c. 6000–5400 cal BC. The Early Neolithic lithic assemblages are characterized by the pressure blade production techniques on high-quality Gargano cherts reflecting important socio-economic and technical mutations that are specific to the Neolithic. Moreover, the almost exclusive reliance on these exogenous cherts emphasizes the social aspects of such networks and reinforces the idea of cultural uniformity of Dalmatian and Apulian Impressed Ware.

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