Work carried out in this laboratory over the past 15 years has resulted in a new classification of the Festuca rubra L. group. The purpose of this note is to describe the only new taxon recognised.

Dipsacus strigosus WiIld., a native of southern Russia and western Asia, was reported as an alien in Britain by Hansen (1963), and a later note by Gerrans (1964) tabulated the characters that separate it from D. pilosus L., which it closely resembles. D. strigosus is most easily distinguished from

in July 1977 of a small thriving colony at an altitude of 480m, GR 19/163.081, just below the outlet of the lochan which lies on the col between Sgurr Scaladale and Tomnaval. The plants were in short turf on the gently inclined grassy slope a little above the steep plunge into Scaladale. They were found

be treated as conspecific, a conclusion reached earlier by Friderichsen (MS note by Rogers 1897 on BM sheet) , Rogers (1900) and, ultimately, Watson (1958). The name nevertheless seems worth retaining at varietal level in view of the interesting difference in range, and the necessary new combination

cm; stock 1·5cm, short, thick; stems numerous, erect, much branched. Lower leaves all shrivelled or eaten by larvae of cinnabar moth (Callimorphajacobaeae) at time of gathering; upper leaves narrowly lanceolate, shallowly lobed or toothed, auriculate. Capitula numerous, ± cylindrical or narrowly

Abstract High-resolution seismic-reflection profiles (3.5 kHz) show that a dis-tinctive, widespread reflection occurs in the sediments beneath Upper Klamath Lake, Oregon. Coring reveals that this reflection is formed by Mazama tephra (MT), about 7 ka in age. The MT horizon is faulted in many places and locally displaced by as much as 3.1 m. Differential displacement of multiple horizons indicates recurrent fault movement, perhaps three episodes since deposition of the Mazama. The pattern of faulting indicates northeast–southwest extension beneath the lake basin.

Implications of thin layers for amplitude variation with offset (AVO) studies

The 3D analytic signal amplitude of a total magnetic inten-sity (TMI) map, introduced by Roest et al. (1992), is widely used in magnetic interpretation as a means of positioning anomalies directly over their sources. This technique is most

SEP has been striving to create reproducible research for many years. Our first attempts at reproducible documents began with the introduction of interactive documents (Claerbout, 1990). We then moved on to putting SEP reports on CDROMs and using “cake ” (Nichols and Cole, 1989) so that the results could be recreated using the author’s own processing flow. Later

The essence of Backus theory (Backus, 1962) is that it allows a bunch of layers to be replaced by a single layer. The new homogeneous medium has elastic properties identical in the long-wavelength limit so that mass and travel-time are conserved, but wavelet shape is not. In this paper I show that for normal incidence plane waves the three elastic layer