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EN
Analysed set of bones cones from two objects (no 11 and 13), excavated on a multi-cultural site in Smrokow, site 17, Kraków County. Materials discovered there can be dated to the II period of the Bronze Epoch, and are associated with the development of the Trzciniec Culture in the loess areas of the Lesser Poland Upland. Animal bone relics from Smrokow were subject to zoological analyses, which consisted of species and anatomical identification, quantitative assessment (bones and specimens), measurements of bones and estimating age, gender and size of animals, as well as observation of traces, patological changes and anomalies in bones. High proportion of domestic mammals bones in the material from Smrokow can indicate the main role played by animal husbandry in providing meat for food. It represents a low horse of the tarpan type, its built resembling that of medium-thick-legged and thick-legged horses.
2
Content available Zbigniew Ryziewicz (1898-1977)
75%
3
Content available Oviraptorosaur tail forms and functions
63%
EN
Oviraptorosaur caudal osteology is unique among theropods and is characterized by posteriorly persistent and exceptionally wide transverse processes, anteroposteriorly short centra, and a high degree of flexibility across the pre-pygostyle vertebral series. Three-dimensional digital muscle reconstructions reveal that, while oviraptorosaur tails were reduced in length relative to the tails of other theropods, they were muscularly robust. Despite overall caudal length reduction, the relative size of the M. caudofemoralis in most oviraptorosaurs was comparable with those of other non-avian theropods. The discovery of a second Nomingia specimen with a pygostyle confirms that the fused terminal vertebrae of the type specimen were not an abnormality. New evidence shows that pygostyles were also present in the oviraptorosaurs Citipati and Conchoraptor. Based on the observed osteological morphology and inferred muscle morphology, along with the recognition that many members of the group probably sported broad tail-feather fans, it is postulated that oviraptorosaur tails were uniquely adapted to serve as dynamic intraspecific display structures. Similarities, including a reduced vertebral series and a terminal pygostyle, between the tails of oviraptorosaurs and the tails of theropods widely accepted as basal members of the Avialae, appear to be convergences.
EN
A detailed osteological analysis of the skull of an Antarctic fish, Chaenodraco wilsoni Regan, 1914 (Channichthyidae, Notothenioidei) was done, focusing on the bone structure and osteological variability. A notable reduction of the ossification was observed, which took place in several ways: replacement of the whole bone with cartilage, only superficial ossification (e.g. in the ethmoid region), separation of the bones by wide cartilage areas (e.g. in the brain case), and reduction of bone dimensions. An extreme case was complete loss of the opisthootic-the first record of this kind within this family of fishes. The reduction of ossification in Ch. wilsoni resulted in high osteological variability that was observed in the case of reduced bones. Instances of asymmetry of paired elements of the skeleton were observed as well.
PL
Przeprowadzono szczegółową analizę czaszki antarktycznego gatunku Chaenodraco wilsoni Regan, 1914 (Channichthyidae, Notothenioidei, Pisces) pod kątem struktury poszczególnych skostnień, jak i zmienności osteologicznej. Zaobserwowano znaczną redukcję skostnień, mającą charakter zastąpienia całych skostnień chrząstką lub tylko powierzchniowego kostnienia (np. w rejonie węchowym), rozdzielenia skostnień szerokimi pasmami chrząstki (np. w obrębie puszki mózgowej), redukcji rozmiarów kości. Skrajnym przypadkiem jest zupełny zanik opisthooticum - stwierdzony po raz pierwszy u ryb tej rodziny. Redukcja skostnień u Chaenodraco wilsoni pociąga za sobą wysoką zmienność osteologiczną, obserwowaną w przypadku kości zredukowanych. Zaobserwowano także przypadki asymetrii parzystych elementów szkieletu.
PL
Zbadanie kilkuset okazów Pygomalus analis (Agassiz) , zebranych przez autorkę w górnym batonie Piły Kościeleckiej (ark. Chrzanów), dało możność :zanalizowania zmian , jakim podlega pancerz tego jeżowca, poczynienia szeregu nowych obserwacji dotyczących morfologii jego tarczy szczytowe] i perystomu oraz wyjaśnienia stosunku do niego formy opisywanej pod nazwą Pygomalus faba (Desor).
FR
Un materiel exceptionnellement abondant (environ 800 specimens) de L`echinide en ąuestion reuni par 1’auteur dans le Bathonien de Piła Kościelecka (feuille Chrzanów), lui a permis de faire des observations detaillees de la variabilite de ses differents caracteres. Caracteristique de l`espece. — Test a contour ovale, retreci vers Tarriere. Ligne de profil longitudinal s’elevant en arc doux d’avant vers l`arriere et atteignant son point culminant dans 1’appareil apical ou un peu pLus en arriere, pour s’abaisser ensuite lentement jusgu^u póriprocte et y tomber plus ou moins a pic. A la facę inferieure le profil est k peu prós rectiligne. Sur les echantillons mesures la longueur varie entre 16 et 35 mm, la largeur etant toujours moindre que la longueur. La valeur. du rapport entre la longueur et la largeur oscille entre 0,89 et 0,98 et celle entre la hauteur et la longueur —r entre 0^2 et 0,79; ce dernier rapport diminue avec raccroissement de la taille des individus. La partie antórieure de 1’appareil apical est placee toujours en avant du centre du test, et la partie posterieure — tout pres du periprocte. Entre les deux parties ii y a, en gónóral, des plaąues supplementaires (fig. 3 du texte polon ais), Ces plaąues existent parfois egalement dans la partie proximale (fig. 4) et la distale (fig. 5) de Tappareil apical. Les variations de la position de deux parties de Tappareil apical sont i-lłustrśes par des chiffres du tableau A (p. 57 du texte polonais), qui expriment le rapport entre la distance de chacune de ces parties du bord antćrieur du test et la longueur totale de celuici. caracteres a la formę typique sans carene (tabl. B) et ne peut nullement en etre se- paree. La meme opinion a śte exprim£e par Beurlen (1934, p. 70). La structure de 1’appareil apical varie peu, seule la paire postćrieure des plaques gśnitales est variable quant 5 leur formę et leur rapport rściproąue (fig. 11). Da/ns certains cas rauteur a pu constater la prśsence des pores genitaux surnume- raires. Le cinquieme porę est alors place tantót sur une plaque oculadre, tantót deux pores sont places sut une seule plaque gśnitale; enfin, sur un seul spścimen, on a constate la preśsence de la cinąuieme plaque genitale, placee au-dessous de la paire posterieure (fig. 12). La partie dis tale de 1’appareil apical comprend toujours deux plaques oculaires allongśes de faęon a encadrer le periprocte (fig. 13). La position des ambulacres du bivium par rapport au periprocte est variable: leurs extrśmites sont placees tantot lateralement, tantót en avant du periprocte (fig. 14), sans gamais perdre toutefois leur jonction avec le periprocte par rintenmediaire des plaques oculaires. Le peristome est tantót et le plus soiwent subpentagonal, tantót pentagonal, et assez rarement arrondi (fig. 15). Parmi les specimens a pśristome pentagonal, 75°/o correspondent a des Lndividus petits, 17,5% seulement a des form es plus grandes. Chez les individus de taille moyenne domine la formę subpentagonale du pśristome. De ces ofoservations on peut conclure que, lors de la croissance de l’individu, la for­mę du peristome change progressivement de pentagonale a la subpentagonale et a Tarrondie (fig. 15). Schemas expliquant les mensurations des distances entre: 1° la partie proximale de l`appareil apical et le bord anterieur du test (a) 2° la partie dis tale de cet appareil et le bord' anterieur du test (b), 3° le peristome et le bord antśrieur du test (c). Fig. 2 (p. 54) Variations de la formę du test — A vus d’en haut, B de profil. Fig. 3 (p. 55) Disposition des plaques supplementaires (pointillśes) entre les parties proximale et distale de l`appareil apical — g plaques genitales, o pi. oculaires, pp periprocte. Fig. 4 (p. 56) Partie proximale de l`appareil apical — d plaque supplementaire, g pl. genitale, m pl. madreporique, o pl. oculaire. Fig. 5 (p. 56) Partie distale de l`appareil apical — b bivium, d plaques supplśmentaires, o pl. oculaire, pp periprocte. Fig. 6 (p. 56) Un ambulacre anterieur — A partie aborale, B partie orale, ps peristome. Fig. 7 (p. 58) Differenciation des pores d’une paire Fragment de la partie anterieure du test — ia interambulacre, na ambulacre impair Fig. 9 (p. 60) Individus a differents stades de croissance vus par la face aborale (A) et de profil (B), Fig. 10 (p. 61) Deux specimens vus du cóte posterieure — A formę typique, B formę „faba”. Fig. 11 (p. 61) Variations dans la disposition des plaques genitales. Fig. 12 (p. 62) Pores genitaux surnumeraires — A et B dans les plaąues oculaires, C deux pores dans une plaąue gendtale, D cinqui&me plaque genitale. Fig. 13 (p. 62) Disposition des plaąues oculaires par rapport au periprocte — b biykim, o plaąue oculaire, pp periprocte. Fig. 14 (p. 62) Schema de la position du biviuim par rapport au periprocte. Fig. 15 (p. 63) Differentes formes du peristome — A pentagonale, B subpentagonale, C arrondie.
EN
The connecting ring in orthoceratids is composed of two calcified layers: an outer spherulitic−prismatic and an inner calcified−perforate. The spherulitic−prismatic layer is a direct continuation of that layer in the septal neck, whereas the calcified−perforate layer is a structurally modified continuation of the nacreous layer of the septal neck. The latter layer is traversed by numerous pores which are oriented either transversally to the siphuncular surface, or have a somewhat irregularly anastomosing course. The connecting ring structure is positively correlated to the dorsal position of the scars of the cephalic retractor muscles. A similar type of connecting ring and a dorsal postion of retractor muscle scars also occur in lituitids, previously assigned to tarphyceratids, and in baltoceratids, previously assigned to ellesmeroceratids. These two taxa are therefore included in the suborder Orthoceratina, which, together with the suborder Actinoceratina, are assigned to the order Orthoceratida Kuhn, 1940.
18
Content available Andrzej Sulimski [1926-1997]
51%
19
Content available The tube wall of Cambrian anabaritids
51%
EN
Celestite/barite−replaced and phosphate−replicated tubes of Early Cambrian anabaritids from the northern part of the Siberian Platform (Anabar Shield) give new evidence on the wall−structure of these enigmatic fossils. The walls consist of fibres, interpreted as reflecting an original aragonitic fabric. Bundles of fibres are arranged in growth lamellae, and the latter form an angle of at least 45° with the inner tube wall. Where the outer tube surface projects into annular flanges, the lamellae have a chevron−like section due to the backwards deflection of the outer parts. Anabaritids are usually referred to the Cnidaria or left without systematic assignment, but earlier suggestions included affinity to the serpulid polychaetes. The chevron structure resembles that previously exclusively known from serpulids, but the presence of internal tooth−like structures in anabaritid tubes, perhaps compromising up−and−down movement through the tubes, continue to make a direct assignment to the Serpulida questionable.
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