Toxicology of a potential molluscicide derived from the plant Solanum xanthocarpum: a preliminary study.

A potential molluscicidal extract, obtained from the indigenous Chinese plant Solanum xanthocarpum (Schrad. and Wendl), was tested for toxicity against snails and fish in static, acute-toxicity tests. The extract had a significant effect on mature and young snails of the amphibious Asian freshwater prosobranch Oncomelania hupensis (Gredler) and also on mature specimens of the freshwater pulmonate snails Biomphalaria glabrata (Say) and Lymnaea stagnalis (Linnaeus). The minimum dose that produced 100% mortality of snails exposed for 48h, 4.321mg/litre, is much less than the threshold, of 100mg/litre, set for a potential molluscicide by the World Health Organization. In contrast, the minimum concentration producing 100% mortality in the fish Gobiocypris rarus (Ye and Fu) was 17.28mg/litre. The extract also limited the extent of water-leaving by snails exposed to it, an important feature for the control of amphibious snails. This extract thus represents a promising plant-derived molluscicide which is worthy of further investigation.

[Study of the correlations between the volumes of the hypophysis, the epiphysis and the subfornical organ to the somatic weight and the volume of the hypothalamus in rodents]. / Etude des correlations liant les volumes de l'hypophyse, de l'épiphyse et de l'osf au poids somatique et au volume de l'hypothalamus chez les rongeurs

The correlations between volume of the hypophysis, of the epiphysis and of the subfornical organ to body weight and volume of the hypothalamus were studied on 193 rodents belonging to 41 species. Concerning the volume of the hypophyseal lobes the regression slopes of Rodentia occupy an intermediate position between those of Isectivora and Prosimians studied by BAUCHOT. The volume of the epiphysis increases more rapidly with the weight of the body than that of the hypophyseal lobes, the volume of the subfornical organ increases on the contrary more slowly.

[Morphometric data on pineal gland of loir (Glis glis) and lerot (Elioyms quercinus) during the annual cycle]. / Données morphométriques sur la glande pinéale du loir (Clis glis) et du lérot (Eliomys quercinus) au cours du cycle anuel

The important involution of the pineal gland of Glis glis and Eliomys quercinus during the months of july and august belongs to a polyglandular involution (anterior lobe of the hypophysis, male and female genital glands) characteristic of estivation.