A possible hydroid from the Lower and Middle Ordovician of Bohemia

A new genus Webbyites from the Lower and Middle Ordovician of Bohemia is described. Its planar, feather-like benthic colonies (or their parts) display possible hydrozoan affinites. Webbyites is interpreted as an inhabitant of the littoral and sublittoral environment, with high energy, oscillating to current zones.     

Policy Design and the Acceptability of Environmental Risks: Nuclear Waste Disposal in Canada and the United States

This article examines the controversial process of developing high-level nuclear waste disposal policy in Canada, with some comparison to experience in the United States. It argues that a policy design perspective can assist in understanding the difficult social and political issues associated with waste disposal and the environmental and health risks that it poses. I examine several critical questions related to such an endeavor and link them to long-term goals of building a sustainable society. Success in formulating and implementing a nuclear waste policy in Canada will depend on the nation's capacity to create requisite processes of public participation. Particularly important are those actions that can help the public understand and assess environmental risks, including related ethical and social issues, and build public trust and confidence in the siting processes and the implementing agencies.     

A new approach to sexual diagnosis in past populations. Practical adjustments from Van Vark's procedure

Determination of sex is a key aspect in the study of past populations. Bias in skeletal sexing is well known, however, and depends upon the completeness of the skeletal remains and the representativeness of reference samples. In order to correct these difficulties, the authors propose practical adjustments to Van Vark's well‐known procedure. Two fundamental aspects are considered to reduce the bias of sex allocation. First, we propose to increase the effectiveness of sexing during the first step (primary diagnosis only from the pelvic bone). Second, to improve the final step (secondary diagnosis from the extra‐pelvic skeleton), we consider posterior probabilities as essential. These two practical adjustments are successfully tested in a sample of known sex and lead to a classification with 94.5% accuracy. These results significantly improve sex determination in archaeological samples and therefore contribute to a better understanding of past populations. Copyright © 1999 John Wiley & Sons, Ltd.