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Zosterophyllum longa sp. nov. is reported from the Lower Devonian Pingyipu Formation, Jiangyou District, northern Sichuan of China. This new plant has vertically elongate sporangia differing from all known species of Zosterophyllum, demonstrating morphological variations in Zosterophyllophytina. New materials of Zosterophyllum yunnanicum from the Lower Devonian Xujiachong Formation, Qujing District, eastern Yunnan of China show that fertile axes of this species are anisotomous or pseudomonopodial or K-shaped in branching. Sometimes fertile lateral axes are very short and bear an axillary axis at the dividing point. Distinct thickening occurs along the whole margin of a sporangium, with sporangial lobes undeveloped. The evolution of Zosterophyllum is tentatively discussed. A biostratigraphic method of Gerrienne and Streel is introduced and applied to dating of the Lower Devonian Xujiachong Formation, which is considered as of the late Pragian-early Emsian.

A new plant, Zhenglia radiata gen. et sp. nov., from the Posongchong Formation (Early Devonian, Pragian age) of the Wenshan District of southeastern Yunnan Province, China is a small herbaceous lycopsid. The aerial branches divide into foliar and fertile stems. The arrangement of the leaf bases on the stem shows lepidodendroid-like phyllotaxy. Possibly the leaf base bears a ligulate pit. The microphyll consists of a swollen, decurrent base, and an entire, linear lamina. The fertile axis is composed of sporophylls arranged helically, forming a compact area similar to cone-like structure. Each sporophyll consists of a widened lateral extension and a distal lamina. The ovoid-elongate sporangia are attached adaxially on the surface of sporophylls. Based on morphological similarities, especially the undivided microphylls, the style of phyllotaxy, the form of the cone-like structures and sporangia, the new lycopsid Zhenglia radiata is placed in the order Protolepidodendrales and a possible evolutionary relationship with the arborescent lycopsids of the Late Devonian and Carboniferous is considered.

We describe the tracheid ultrastructure of Hsua deflexa from the Lower Devonian (upper Pragian–lower Emsian) Xujiachong Formation, Qujing District, Yunnan Province, China. Scanning electron microscopy study of fusainized and permineralized tracheids shows that they are of G‐type, bearing many irregularly distributed perforations. The cell wall consists of a decay‐resistant inner part lining the cell lumen and a nonresistant outer part. The resistant inner part, i.e., the assumed heavily lignified secondary wall, is continuous over the poorly lignified outer part that comprises the primary wall and discontinuous secondary wall. It forms the annular thickening over the discontinuous secondary wall. The heavily lignified secondary wall may be divided into three layers. Minute perforations occur on the entire heavily lignified secondary wall, i.e., between and on the thickenings. Concerning the distribution, density, and diameter of perforations, G‐type tracheids of H. deflexa share some characters of S‐type ...

New fossils of the early Devonian plant Eophyllophyton bellum provide morphological and anatomical information that contributes to an understanding of the origin and early evolution of the megaphyll. These earliest leaves are characterized by leaf divisions, apparently arranged in several planes, that possess branching venation and a mesophyll of longitudinally elongate cells lacking differentiation into palisade and spongy layers. These features support the hypothesis that the megaphyll was derived from an axial branching system. The small size and deeply incised margin of these leaves indicate an adaptation to an environment of heat stress and high concentration of atmospheric CO2. Whereas the available evidence indicates that the megaphyll evolved during the early Devonian, a period of harsh environmental conditions, the evolution and radiation of larger megaphylls was apparently correlated with a massive drop in atmospheric CO2 during the late Devonian and early Carboniferous.

Fossil plants Hedeia sinica Hao et Gensel 1998, Huia gracilis Wang et Hao 2001 and Guangnania cuneata Wang et Hao are described from the Lower Devonian Xujiachong Formation, the Qujing district, eastern Yunnan, China. They contribute to our knowledge of the flora in this district. Based on the occurrence of common plants (Hedeia, Huia, Guangnania and Zosterophyllum australianum) and their horizons, it is proved for the first time that the mid-lower assemblage of the Xujiachong flora is comparable with the Early Devonian ((late) Pragian) Posongchong flora of southeastern Yunnan and the upper Baragwanathia flora of Australia. In view of this fact and the stratigraphic sequence, the mid-lower part of the Xujiachong Formation is considered to be of (late) Pragian age. Through comprehensive analyses of plant, bivalve and fish assemblages and the lithology, the upper part of the Xujiachong Formation is dated to be of early Emsian age. The Xujiachong flora belonged to the northeastern Gondwana palaeophytogeographic unit during the Early Devonian. The early Emsian assemblage of this flora inherited the characters of the Posongchong flora and also exhibited the endemic elements. Belonging to different phytogeographic units, the Xujiachong and Posongchong floras differ from the coeval flora of the Laurussian palaeocontinent. The Xujiachong flora is comparatively simple in composition, while the Posongchong flora has abundant and highly diversified endemics. The disparity between them has resulted from the different environments.

This paper presents silicon proved ESD protection circuit for RFID transponder using 180nm CMOS process. The circuit can also be reused for the functions of rectifier and amplitude limiter. Such method not only reduces RFID transponder's area but also enhances the ESD level remarkably. The test results show that it can provide 8kV human body mode (HBM) ESD protection ability which is especially useful during the manufacturing, transporting and packaging of RFID tag chip.

A new genus and species, Polythecophyton demissum Hao, Gensel and Wang, is described from the Posongchong Formation of Pragian age in the Wenshan district of southeastern Yunnan. This plant consists of major axes, which divide anisotomously to produce irregularly to helically arranged lateral branches. Lateral branches dichotomize once, producing a pair of curved axes; each may dichotomize again, and then produce a series of short, pendulous, lateral fertile systems via unequal bifurcations. Each fertile system may initially bifurcate, and then each component bears 3–4 alternately arranged, short axes terminated by numerous slender fusiform sporangia borne in pairs or in groups of three or four. Collectively, the fertile system is umbrella-like in outline and sometimes bilaterally symmetrical, with a convex upper contour and nearly even lower margin because all sporangia terminate at almost the same level. In some characteristics i.e. shape of the fertile system, type and attachment of sporangia, Polythecophyton shows similarities with Hedeia Cookson, but it differs in its more complex, mostly pinnate distal branching pattern and its pendulous form. Polythecophyton also is similar in some aspects of branching, sporangial morphology, and sporangial attachment to aneurophytalean progymnosperms; in the absence of anatomy and vegetative regions, we currently regard it as Euphyllophytina incertae sedis sensu Kenrick and Crane (1997) . Given its early age, it is of interest in considering evolution of progymnospermous branching patterns, especially in fertile regions. The discovery of this new plant in China demonstrates further variation of plant traits in the northeastern Gondwana phytogeographic region. The architecture of the new plant is of interest because of the sparsity of plants allied to euphyllophytes in this region and its resemblance to aneurophytaleans.