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Tellima grandiflora, a herbaceous, diploid (2n = 14) perennial, is distributed from the peninsula and panhandle of Alaska to central California. Restriction site variation of chloroplast DNA was surveyed in 51 populations representing the geographic range of T. grandiflora using 20 endonucleases. Two well‐differentiated clades of populations differing by 19 restriction site mutations and several length mutations are geographically structured. A northern group comprises populations from Alaska to central Oregon; populations from central Oregon to San Francisco, California, form a southern group. The southern lineage of the monotypic Tellima appears to have obtained its chloroplast genome via ancient hybridization with a species of Mitella. Although northern and southern lineages have well‐differentiated chloroplast genomes, populations of T. grandiflora show a high degree of genetic similarity of nuclear‐encoded allozymes; furthermore, no apparent morphological differences characterize the lineages. Significantly, several populations of T. grandiflora that possess the typical southern chloroplast genome also occur disjunctly on Prince of Wales Island, Alaska, and the Olympic Peninsula, Washington. Because both areas are proposed glacial refugia, we suggest that past glaciation may have created discontinuities in the geographic distribution of T. grandiflora. Following glaciation, migration of once‐isolated populations possessing different chloroplast genomes resulted in the formation of a continuous geographic distribution with a major organellar discontinuity. Additional support for this hypothesis is provided by the presence of well‐differentiated northern and southern chloroplast DNA lineages in Tolmiea menziesii, a species having a geographic distribution and life history traits similar to those of Tellima.

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This article will present a single case study of the acoustic attributes of sound production techniques that are involved in the expansion of performance practice with the violin. In this study, four elements were chosen from the multidimensional network involved in playing a normal tone, and then each was intentionally decoupled from ordinario. These elements (bow speed, bow placement, bow angle, and bow portion) were scaled between minimal and maximal values for any single parameter. Then, between minimal and maximal values, a series of scalar degrees were chosen to more or less uniformly link these extremes. This article will present acoustical attributes of these methods and discuss implications for musical usage. This study found that decoupling of any single parameter will result in perceptible differences that range from timbral to dynamical (sound) class change.