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The theoretical concept of the biological species and the multidimensional species category, as currently applied by a majority of ornithologists and by many other biologists, replaced the typological-morphological species concept during the first half of this century and became a central tenet of the synthetic theory of evolution. The concept of biospecies is a 'horizontal' concept referring to contemporary reproductive communities at any particular period, e.g. the Recent period or any other time level of the geological past. Historical 'species' concepts as applied by cladists and palaeontologists refer to artificially delimited portions of 'vertical' phyletic lineages for which the application of the term 'species' causes severe problems. Discussions would be simplified if the concept and term 'species' was to be restricted to cross sections of phyletic lineages at any time level and a separate taxonomy outside the Linnaean system of genera and species was to be conceived to deal with phyletic lineages. Under each of the theoretical species concepts, species taxa are assigned broadly to intermediate or narrowly defined taxonomic species categories. Ornithologists of the 19th century applied morphological species concepts, emphasizing morphological character differences between species (rather than distinctness) and the fertility of con specific individuals (rather than the isolation from non-conspecific populations). Nearly all leading museum ornithologists in 19th-century Europe delineated monotypic Linnaean species, whereas the explorer-naturalists of the Gloger-Middendorff school (including Panas, Faber, Gloger, Nordmann, Middendorff, Schrenck, Radde, as well as Schlegel and Blasius) delimited widely circumscribed species taxa. Their researches in the vast territories of eastern Europe, Siberia and the Far East from the late 18th century to the 1880s and, in particular, their rich specimen material, demonstrated direct intergradation of many taxa (geographical varieties) of birds, thus revealing the conspecific nature of numerous narrowly conceived morphospecies previously described by museum workers. The ornithologists of the Gloger-Middendorff school also studied several conspicuous phenomena of geographical character variation in birds (and mammals) across Eurasia, especially plumage colouration (and pelage) and body size, but none of them was an evolutionist. They an adhered to a typological-creationist theoretical species concept. During the late 19th century, the museum specialists' taxonomic notion of narrow morphospecies dominated systematic ornithology in Europe, overtaking the work of the naturalists of the Gloger-Middendorff school, which fell into oblivion. The ornithologists of the Bairdian school in North America (Baird, Coues, Allen, Ridgway) further developed the concept of subspecies after the 1850s and especially from the 1870s onward. Their views were fully in accord with Darwin's theories of evolution' thus they defined the subspecies in a somewhat simplified manner as 'nascent species': These ornithologists were able to base their studies on collections of extensive specimen material which they had obtained during a series of exploring expeditions across the North American continent. Their studies led to the discovery of many aspects of both individual and geographic variation in birds. There are interesting historical similarities between the coinciding taxonomic interpretations and the comparable application of fairly broad limits of morphospecies by the North American ornithologists and the earlier exploring ornithologists in Europe, arrived at Independently by these, research groups, The study of specimens in 'series' (,suites'), beginninng with the naturalists of the Gloger-Middendorff school and, in particular, with the naturalists of the Bairdian school in North America, eventually led to the overcoming of the prevating typological view of variation and the development of 'population thinking'. Influenced by the work of Henry Seebohm in Britain and that of the North American ornithologists, Hartert in England and Kleinschmidt in Germany jointly succeeded in overcoming the strong opposition of the leadi.ng ornithologists in Europe during the 1890s and early 19008 and introduced a concept which soon developed into the biological species concept through the work of Stresemann, Rensch, and in particular, Ernst Mayr. Hopefully, ornithologists will continue the study of taxa at low, intermediate and high levels of microtaxonomic differentiation and will identify the subspecies groups, biological species and the biogeographical species in the world's avifaunas. Cladistic analyses will provide historical {'vertical'} overviews of phyletic lineages at different taxonomic levels.
The genus Maculinea van Eecke, 1915 (Lepidoptera: Lycaenidae) from the East Palaearctic Region
(1994)
We revise the classification of taxa belonging to the genus Maculinea from the East Palaearctic Region. In this region, in addition to the well-known three species: M. arion (Linnaeus, 1758), M. ationides (Staudinger, 1887) and M. teleius (Bergstriisser, [1779] 1778-1780), two additional species occur: M. alcon ([Denis & Schiffermiiller], 1775) (upper and middle Amur River, Primor'e, China Northeast/Manchuria and North Korea) and M. kurentzovi sp. nov. (upper and middle Amur River, Primor'e, China Northeast and North Korea). Lycaena kondakovi (Kurentzov, 1970) described from Primor'e is a composite species: the lectotype if' designated here represents an East-Asian subspecies of M. alcon, but its single paralectotype is a female to be assigned to M. kurentzovi sp. nov. Only limited numbers of specimens have been known with M. alcon kondakovi from lowlands of "Far-Eastern" Russia and China Northeast, but in North Korea we found a conspicuous allied taxon arirang nov. (female unknown), which we treat here as a highland subspecies of M. alcon but which may actually represent a good species. Of kurentzovi, we have found a series of specimens which have so far been mostly confused with M. teleius in various collections. We treat Glaucopsyche xiaheana Murayama, 1991 from western Gansu as a subspecies of M. arion along with other subspecies from the central and western parts of China: M. adon philidor (Fruhstorfer, 1915) from the east end of the Qilian Range as well as Mongolia, the type locality, and M. arion inferna nom. nov., a replacement name for Lycaena talsienluica (OberthUr, 1910) (praeoccupied) from Tibet, Sichuan and Qinghai. Because of the similarity of male genitalia and existence of intermediate forms, we regard M. sinalcon Murayama, 1992 described from Qinghai as a subspecies of M. teleius despite a few significant characteristics of the holotype. East continental Asia may be regarded as the headquarter of the genus Maculinea.
Introductory chapters on the geography, vegetation and history of botanical ex loration are followed by a catalogue of 331 species of wild vascular plants, 90% of which represent first records for the island. Synonymy, references, localities and ecological data are given for each species in a condensed form. The taxonomy, nomenclature and distribution of some taxa are discussed; in one case (Silene cythnia) a drawing and a distribution map are supplied. Nomenclatural novelties are validated in the genera Centaurea, Matricana, Melica (by W. Hempel) and Trifolium. A phytogeographical and ecological analysis of the flora demonstrates its striking banality and the unexpectedly high proportion of anthropophytes. No pliytogeographical link with tlie other E. Aegean Isiands and Anatolia exists, but there are some affinities with the Cyclades. The observations are consistent with the hypotliesis of a long insular isolation leading to a strong depletion or even destruction of the original flora, which has been replaced by long-distance dispersed and anthropophytic elements.
The primary subdivisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, and myelencephalon) have similar relations and comparable functions in all vertebrates. Accordingly, the landmarksthat define their boundaries can be regarded as reliable for following their development. On the basis of a more complete series of well preserved embryos than has been available hitherto, we present evidence that the subdivisions of the adult brain can be traced back to neural-fold stages in which a series of growth centers can be recognized, differing from one another in form, size, and relations. The possibility of following the constrictions between the various subdivisions throughout development has been doubted by some, notably Hochstetter (1919). At present we are convinced that they can be distinguished if certain criteria are followed. These are: (a) constrictions involve the neural tube as a whole; (b) constrictions do not give rise primarily to any neural centers; (c) constrictions change in relative length and width, and in certain stages they become inconspicuous in models. The anatomical descriptions of progressive stages of development have important practical implications. It is known, for example, that congenital malformations of the central nervous system in man are common and that they are responsible for a substantial portion of fetal wastage as well as infant mortality and morbidity. In certain patients comprehensive clinical studies may indicate the underlying abnormality, such as dysraphism, arhinencephaly, hypoplasia of the cerebellum. or absence of the corpus callosum. In addition, anatomical examination of the affected brains may reveal in detail such abnormalities as lyssencephaly, polymicrogyria, or other cortical dysgeneses. These very complex cerebral malformations can only be understood and unraveled in the light of normal development. An investigation of early development of the brain must necessarily begin with a stage in which the major landmarks of the adult brain can be readily identified.As progressively younger stages are analyzed certain landmarks can no longer be recognized, although others persist at least to the third week of gestation. We believe that the evidence on which this study is based can be followed more satisfactorily in this inverted sequence, and the detailed description is so presented. It is followed by a summary of the sequence of events written in the conventional manner, as far as the eighth week of gestation.
Over 6260 fungi have been isolated from samples of feathers, nests, pellets, droppings, cloaca contents and visceral organs of 92 species of free-living birds in Czechoslovakia and Yugoslavia. Several species have been obtained of fungi pathogenic to homeotherms, poikilotherms and plants, and many fungi recorded belong to the toxinogenic species.Cellulolytic fungi have participated with 44.3 % in the total number of fungi, and keratinolytic fungi with 18.3 %. The thesis has been confirmed that habits (specific bionomics) of the birds influence,. to a certain degree, the distribution of the fungi among them. According to the results of this study, the fungi may conveniently be divided into three categories with respect to the character of their distribution and dispersal by free-living birds: (1) euryornithochous fungi , the occurrence of which in birds is undetermined by the birds' habits (ubiqitous species: Aspergillus flavus, Gliocladium roseum, Rhizopus. nigricans, Trichothecium roseum); (2) mesoornitohochorous fungi, the occurrence of which in birds is determined to a certain degree by the birds' habits (e. g., Aphanoascus fulvescens, Arthrodermcr curreyi, Chrysosporium keratinophilum, C. tropicum, Mucor hiemalis); (3) stenoornithochoruss fungi, which are associated with certain habit groups of the birds only (e. g., Aphanoascus terreus, Arthroderma ciferrii, A. tuberculatum,.Aspergillus fumigatus, Chrysosporium pannorum, Ctenomyces serratus). The importance of free-living birds in the spreading of pathogenic organisms has also been discussed from a more general point of view, particularly with regard to several epidemiologically important aspects of bird ecology such as synanthropism, migration (making possible a long-range carriage of pathogens or infected vectors), colonial breeding or mass roosting.
Birds are characterized by pneumatization of their skeletons by epithelial diverticula from larger, air-filled cavities. The diverticula-or 'air sacs'-that invade the postcranium result from outgrowths of the lungs; poslcranial pneumaticity has been very well studied. Much more poorly understood are the air sacs that pneumatize the skull. Study or craniofacial pneumaticity in modern birds (Neornithes) indicates the presence of two separate systems: nasal pneumaticity and tympanic pneumaticity, The lacrimal and maxillary bones arc pneumatized by diverticula of the main paranasal cavity, the antorbital sinus. There are five tympanic diverticula in neornithines that pneumatize the quadrate, articulare and the bones of the braincase. The pneumatic features of the following six genera of Mesozoic birds are examined: Archaeopteryx, Ellaliornis, Baplomis, Parahesperornis, Hesperornis and lchthyornis. Despite the 'archaic' aspect of most of these birds, many of the pneumatic features of neornithines are found in .Mesozoic birds and are considered primitive for Aves. The phylogenetic levels at which most of the avian pneumatic features arose within Archosauria are uncertain. Until the phylogenetic levels at which homologous pneumatic features arose are determined, it is unwise to use most pneumatic characters in the discussion of avian origins. Within avian phylogeny, Ornithurae and Neornithes are well-supported by pneumatic synapomorphies. There is a trend towards reduction of craniofacial pneumaticity within Hesperornithiformes. Witthin Neornithes, four derived pneumatic characters suggest that the Palaeognathae (ratites and tinamous) is monophyletic.
Dr. Nonfin (1931) in his book on the "Biology of the Amphibia", while discussing the inter-relationships of Pelobatidae, divides the family into Megophrynae, Pelobatinae and Sooglossinao und points out that among these three "the most primitive genus in the sub-family is the wide spread Megopluys or Megalophrys (including Leptobrachium)". ...