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2019 ◽  
Vol 46 ◽  
pp. 352-374
Author(s):  
Sonja Kačar

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.


2019 ◽  
Vol 46 ◽  
pp. 352-374
Author(s):  
Sonja Kačar

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.


Phytotaxa ◽  
2018 ◽  
Vol 356 (1) ◽  
pp. 61 ◽  
Author(s):  
HONG-BO JIANG ◽  
RUNGTIWA PHOOKAMSAK ◽  
DARBHE JAYARAMA BHAT ◽  
SEHROON KHAN ◽  
ALI BAHKALI ◽  
...  

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.


1979 ◽  
Vol 57 (8) ◽  
pp. 958-970 ◽  
Author(s):  
Gar W. Rothwell ◽  
James F. Basinger

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.


1978 ◽  
Vol 26 (4) ◽  
pp. 515 ◽  
Author(s):  
GT Kraft

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.


1973 ◽  
Vol 51 (11) ◽  
pp. 2033-2036 ◽  
Author(s):  
Terrence M. Hammill

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.


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

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