The internal morphology of fixed specimens of Antarctic pycnogonids WDS examined. Theories postulated during the course of these histological studies were then tested and modified by observations on live material and specimens fixed specially for histochemistry on visits both to the Arctic and d Antarctic. Live material was also transported back to Britain from these regions and cultured in refrigerated marine aquaria. The digestive system was studied in considerable detail. It is suggested that digestion is intracellular with gut cells changing their morphology during their lifetime. Embryo cells develop into Absorptive cells which at some stage take up a glandular appearance but not a glandular function. There are therefore two gut cell types, 'Embryo' and 'Absorptive/glandular'; this is in disagreement with some previous authors who separate the latter. The rele of the gut cell in the light of present day lysosome theory is discussed and a re-interpretation of work by previous authors suggested. It is found that the digestive process is slow and the prey tastes of the species studied, catholic. Furthermore, it is found that some species can survive for long periods without appearing to feed. Suggestions are made as to the significance and mechanisms of these phenomena. Mass transport in the body cavities is considered flnd compared with that of Hydra, an animal with which previous authors have made comparisons; - their philosophy is questioned. Blood flow, heartbeat and intestine movements are also considered and suggestions for future studies made. The role of blood itself is studied a possible clotting system described. Preliminary experiments on blood electrophoresis and chromatography indicate that such techniques may be useful in clarifying some complexities of pycnogonid classification and might provide a means by which future workers in the field might better link nutritional state, mass transport, digestion and external environment conditions.

Para espécies de hortaliças há carência de informações a respeito de metodologias que forneçam, de forma rápida e segura, dados sobre a qualidade de sementes, haja visto a importância econômica e a alta tecnologia empregada na produção dessas espécies. Diversas técnicas têm sido propostas para avaliar a morfologia de sementes e outros parâmetros relacionados ao seu potencial fisiológico e, entre elas, pode-se citar o uso de imagens radiográficas e análises computadorizadas de imagens de plântulas. Com isso, objetivou-se com a presente pesquisa, estudar a relação entre a morfologia interna observada com auxílio de imagens radiográficas e a qualidade de sementes de cebola, além de verificar a possibilidade da utilização do sistema computadorizado de imagens de plântulas (SVIS® - Seed Vigor Image System) para detectar diferenças de vigor entre lotes de sementes e comparar com as informações fornecidas pelos testes de vigor tradicionalmente utilizados. Para isso, foram utilizadas sementes de dois cultivares de cebola, com cinco lotes cada. O estudo foi realizado em dois ensaios, em que o primeiro consistiu no estudo do teste de raios X e o segundo na utilização do SVIS® para análise de plântulas. As sementes do segundo estudo foram analisadas no decorrer de doze meses de armazenamento, com avaliações semestrais. Após a análise dos resultados, conclui-se que a morfologia de sementes de cebola dificulta a análises de imagens radiográficas, mas o uso dessas imagens permite a identificação de malformações, que estão relacionadas com plântulas anormais e/ou sementes mortas; o SVIS® é eficiente para identificar diferenças de vigor entre lotes de sementes de cebola; a avaliação com o SVIS® deve ser realizada aos cinco dias após a semeadura. / For vegetables there is a lack of information about methodologies which provide, in a quick and safe way, data on seed quality, given the economic importance and the high technology used in the production of these species. Many techniques have been proposed to assess the morphology of seed and other parameters related to their physiologic potential and, among them, we can mention the use of radiographic imaging and computerized imaging analysis of seedlings. The aim of the present research was to study the relationship between the internal morphology observed with the aid of radiographic images and the quality of onion seeds, and to investigate the possibility of using the computerized system of seedling images (SVIS® - Seed Vigor Image System) to detect vigor differences among seed batches and to compare with the information provided by the vigor tests traditionally used. Five batches of two different varieties of onion seeds were used. The study was carried out in two trials, wherein the first essay consisted on the study of the radiographic images and the second one consisted of the use of SVIS® for seedling analysis. The seeds of the second essay were stored for twelve months and analyzed at each six months. It is concluded that the onion seed morphology impairs the analysis of the radiographic images, but the use of it allows to identify defects, which are related to abnormal seedlings and/or dead seeds; SVIS® is efficient to identify different levels of vigor among onion seed batches; the assessment using SVIS® must be done at the fifth day after sowing.

Para espécies de hortaliças há carência de informações a respeito de metodologias que forneçam, de forma rápida e segura, dados sobre a qualidade de sementes, haja visto a importância econômica e a alta tecnologia empregada na produção dessas espécies. Diversas técnicas têm sido propostas para avaliar a morfologia de sementes e outros parâmetros relacionados ao seu potencial fisiológico e, entre elas, pode-se citar o uso de imagens radiográficas e análises computadorizadas de imagens de plântulas. Com isso, objetivou-se com a presente pesquisa, estudar a relação entre a morfologia interna observada com auxílio de imagens radiográficas e a qualidade de sementes de cebola, além de verificar a possibilidade da utilização do sistema computadorizado de imagens de plântulas (SVIS® - Seed Vigor Image System) para detectar diferenças de vigor entre lotes de sementes e comparar com as informações fornecidas pelos testes de vigor tradicionalmente utilizados. Para isso, foram utilizadas sementes de dois cultivares de cebola, com cinco lotes cada. O estudo foi realizado em dois ensaios, em que o primeiro consistiu no estudo do teste de raios X e o segundo na utilização do SVIS® para análise de plântulas. As sementes do segundo estudo foram analisadas no decorrer de doze meses de armazenamento, com avaliações semestrais. Após a análise dos resultados, conclui-se que a morfologia de sementes de cebola dificulta a análises de imagens radiográficas, mas o uso dessas imagens permite a identificação de malformações, que estão relacionadas com plântulas anormais e/ou sementes mortas; o SVIS® é eficiente para identificar diferenças de vigor entre lotes de sementes de cebola; a avaliação com o SVIS® deve ser realizada aos cinco dias após a semeadura. / For vegetables there is a lack of information about methodologies which provide, in a quick and safe way, data on seed quality, given the economic importance and the high technology used in the production of these species. Many techniques have been proposed to assess the morphology of seed and other parameters related to their physiologic potential and, among them, we can mention the use of radiographic imaging and computerized imaging analysis of seedlings. The aim of the present research was to study the relationship between the internal morphology observed with the aid of radiographic images and the quality of onion seeds, and to investigate the possibility of using the computerized system of seedling images (SVIS® - Seed Vigor Image System) to detect vigor differences among seed batches and to compare with the information provided by the vigor tests traditionally used. Five batches of two different varieties of onion seeds were used. The study was carried out in two trials, wherein the first essay consisted on the study of the radiographic images and the second one consisted of the use of SVIS® for seedling analysis. The seeds of the second essay were stored for twelve months and analyzed at each six months. It is concluded that the onion seed morphology impairs the analysis of the radiographic images, but the use of it allows to identify defects, which are related to abnormal seedlings and/or dead seeds; SVIS® is efficient to identify different levels of vigor among onion seed batches; the assessment using SVIS® must be done at the fifth day after sowing.