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A diverse Ordovician assemblage of juvenile bryozoan colonies, with external phosphatic coatings allowing chemical extraction from the rock, shows a morphologic series probably corresponding to evolutionary step-by-step suppression in the formation of the external colony wall. Its formation was initially delayed leading to formation of the common bud (advanced corynotrypids). Then the permanent double-walled colony organization developed along the colony margin (Flabellotrypa-like). In the following evolutionary stage, the external wall was secreted only at the conical creeping stage immediately following ancestrula (typical rhabdomesines). With subsequent evolution the external wall completely disappeared, and the double-walled ancestrula grew vertically (advanced rhabdomesines and phylloporinids). This kind of the early astogeny characterizes also the oldest phyllodictyid cryptostome Prophyllodictya, studied in serial peels. Flabellotrypidae fam. n., Mojczatrypa halysitoides gen. et sp. n., Kielceporidae fam. n., Kielcepora ornata gen. et sp. n., Ojlepora gen. n., and Kielanopora gracilis gen. et sp. n. are proposed.
The film shows, in a comparative way, the use of high speed filming method technique in the analysis of hydraulic press testing of the compressive strength of six samples of limestone and four samples of dolomite from various geological periods. The course of changes occuring during the process of testing of compressive strength was recorded with a Hyspeed camera at 400 frames per second, comparative counting of frames of individual phases was done with an analyzer manufactured by J. Hadland, slowing down the picture 25 times. Compared to the standard readout of results from a dynamometer integral to the hydraulic press, whose hand recoils after the tested materials’s failure, the use high speed filming method is much more advantageous, lenghening the time of visual observation and inspection and recording of details of the disintegration and propagation of samples fragments with varions dynamics, both in time and in space, until they come to final rest. The film method of quantitative analysis, i.e. counting of frames of individual phases, allows more detailed assessment of the properties of the tested sample and creates a wider, more universal scope of comparison, both between individual samples of a given type of rock, and between types of a given geological period. The conclusions have shown that these are not converging values, which depends on structure and texture, whose details were most differentiated during the process of fracturing and propagation of the sample. The use of the high speed filming technique is a principal assessment criterion within the scope of a wide range of obtaining qualitative properties. This facilitates the possibility of qualifying with respect to the most accurate suitability in appropriate brandies of the national economy. This corresponds to visual inspection of steel alloys fusing.
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The graptoloid prosicula (conus and cauda) forms the first part of the growing colony, and was probably secreted during a single continuous episode of growth. The wall is composed of a central unit of criss-cross fibrils (fusellar fabric), interlaced with parallel fibrils whose grouping appears as the spiral line (spiral line fabric). The conus is lined with a granular or felted sheet (sheet fabric). The diaphragm, at the apex of the conus, appears to be formed of fusellar fabric. The cauda is formed of fusellar and spiral fabrics with a central cavity apparently not open to the conus interior. An outer layer (diamond, mesh fabric) of fibrils forming a diamond mesh covers both conus and cauda, and is itself overlain by longitudinal rods. The apex of the cauda is formed of a second domed diaphragm of criss-cross fibrils, covered by a sheet fabric. The nema is extended distally as a series of finger-shaped increments, overlain by bandages. An outermost layer of clustered fibrils (stellate fabric) is occasionally present, lying on, or formed by a modification of, the diamond mesh fibrils of the conus.
Each developmental phase of the Givetian to Frasnian carbonate complex of the southern Holy Cross Mts is marked by distinctive calcareous microbiota. The Stringocephalus bank deposits contain a very rich, well-preserved microproblematica (of chiefly ?algal origin) dominated by calcispheroids, and many calcified cyanobacteria and green algae with filamentous Bevocastria, tubiform Devonoscale, and charophyte Trochiliscus. In the late Givetian biostromal complex more sparse microfossil associations occur, with the exception of locally abundant semitextulariid foraminifera (mainly Nanicella) and tubiform dasyclad(?) Jansaella. Also in the Frasnian back-reef facies, only limited and poorly preserved calcispheroids are identified. Contrarily, reef- and fore-reef microbiotas were present in great profusion. Microbial mats (including calcified cyanobacteria Renalcis and Sphaerocodium), associated with locally frequent solenoporids and multichambered foraminifera (Nanicella, also many nodosariids in the later Frasnian) played a significant depositional role and evidence progressive shoaling conditions within the Dyminy reef-complex.
Late Visean ostracod assemblages from three regions of southern Poland strongly differ in contribution of species and specimens of the three main superfamilies. In the Cracow area, ostracods from the clays of Orlej are basically different from those from the limestone section of Czerna located only ten kilometers eastward but are similar to ostracods from the Lublin region. The kloedenellacean-bairdiacean dominant fauna of Czerna is representative of nearshore conditions, as opposed to the offshore Orlej bairdiacean-kirkbyacean fauna.
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