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Abstract. Abyssal microfloral succession induced by experimental organic degradation was investigated. Notable changes in amounts and compositions of short‐chain (C9‐20) sediment fatty acids were observed, which indicated the shift of sediment microflora. Biomarker fatty acids for methanotrophs and sulfate‐reducing bacteria dominated. Resultant fatty acid compositions were most closely related to those from a nearby methane seep harboring a dense Calyptogena colony; the clams were also seen in close vicinity of the deployed organic mass. These observations suggest that the organic degradation on the bathyal seafloor stimulates the formation of methanotrophic and thio­trophic microflora, resulting in the formation of a methane‐seep‐type benthic community.

The authors review the impact of research hypotheses and subject characteristics on the validity of observations. The research published over a 2-year span in 4 special education journals is then reviewed to ascertain the extent to which observer bias is a problem in special education research. It was found that about half of the research articles ran substantial risk of biased observation; in about three-fourths of these articles, no precautions were taken by the researchers to safeguard the validity of their observations.

A biological community was discovered in the Northern Okushiri Ridge, northeastern Japan Sea. The community was closely associated with sea‐floor fissures, and presumed to be supported by methanotrophic and/or thiotrophic bacterial production. Sediments inside of and in the vicinity of the fissures were collected, and the short‐chain (C9–20) sediment fatty acids were analyzed for amounts and compositions. The fatty acid compositions were compared with those from a known methane seep and a submarine volcano in the Sagami Bay, central Japan, and from a whale skeleton at the Torishima Seamount, northwestern Pacific Ocean. As a result, a close relationship between the sediments from the Northern Okushiri Ridge, the known methane‐seep, and the whale skeleton was found. This finding represents the first discovery of methane seepage and associated biological communities in the Japan Sea. This also supports the hypothesis that the eastern margin of the northern Japan Sea is at the early stage of new subduction.

Eleven academically handicapped and 18 nonhandicapped members of a fourth-grade class participated in a six-week study designed to investigate the social comparison behavior of mainstreamed students. An auditing procedure was used that allowed students to audit their own performance and that of all classmates on daily arithmetic assignments. Auditing was done on a computer terminal which was installed in the classroom; the computer kept a daily record of auditing choices. Under the assumption that classmate auditing was an act of social comparison, computer records were analyzed to determine whether handicapped children made comparisons as often as nonhandicapped peers and whether or not they chose to compare with classmates similar to themselves. Results indicated that the handicapped students on the average audited classmates more often than nonhandicapped peers; however, this difference was not statistically significant. Close examination of auditing choices indicated that handicapped students did not prefer to compare with other handicapped classmates nor with classmates who performed similarly. Handicapped students who ranked lowest on the comparison measure clearly preferred to compare with high-ranked classmates. The results are compared with results of a previous investigation, and their implications for mainstreaming and the study of social comparison among children are discussed. Major assumptions and limitations of the study methods are also critically examined.