Surgery for these mostly benign tumours is very challenging and requires a multidisciplinary team. Perinatal planning allows appropriate management at birth, decreasing the risk of airway obstruction. Surgery is the mainstay of treatment of teratomas.

To verify the functional hypotheses that link, in vertebrates, the skeletal mass (Ms) to the total body mass (Mt), the skeletons of 75 adult specimens of anuran amphibians (Mt = 5–400 g) belonging to 7 species, aquatic, semiaquatic, or terrestrial (5 Rana, Bufo americanus, and Xenopus laevis), have been extracted by enzymatic maceration, and air-dried. Covariance analyses show significant differences in position, but not in slope, between the anuran species in the specific allometric relationships [Formula: see text]. A Spearman rank test indicated a highly significant relationship between the regression-line position and the level of species infeodation to the aquatic habitat. The relationship is more evident for the Ranids. The relative mass of the skeleton in terrestrial species (e.g., R. sylvatica: 4.4%) can be twice that of aquatic species (e.g., R. septentrionalis: 2.3%). For the 75 anuran specimens, the calculated allometric equation, [Formula: see text], is very close to the one already established for teleost fish. When R. septentrionalis is excluded, the allometric coefficient becomes significantly inferior to unity (b = 0.928). It is concluded that the relative mass of the skeleton is linked with individual and species body size but that the life mode has a preponderant influence. A model that takes into account intra- and inter-specific variations in body mass is developed to predict the skeletal mass of an anuran.

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The riparian vegetation of about 30 islands located upstream of lake Saint-Pierre has been analysed. Eleven natural vegetation units were identified, described and defined along with five units of human origin and six agricultural types. The aquatic habitat is characterized by a Vallisneria americana plant community-type. In the semiaquatic floodland habitats, four community-types were present: a Sagittaria latifolia, a Sparganium eurycarpum, a Phalaris arundinacea, and a Scirpus pedicellatus type. The wetlands were characterized by an Acer saccharinum – Ulmus americana – Fraxinus pennsylvanica forest. Both vegetational analysis and fluctuations of the superficial water table pointed to the existence of four variants in this last type of riparian forest. Those are respectively a Matteuccia struthiopteris, a Laportea canadensis, an Onoclea sensibilis, and a Rorippa amphibia variant. Granulometric and pedologie analyses of typical soil samples are also presented and discussed.