Suvliniary The work was carried out primarily to check the validity of the Devonian geomagnetic field axis as determined by Stubbs (1958) from measurements on uncleaned igneous samples. For this new survey, samples of six lava flows were collected from the Lome Plateau (west Scotland) and ten flows were sampled from the Stonehaven-Montrose area and Tayside (east Scotland). Directions of magnetization were measured after treatment in successively applied a.c. magnetic fields up to a peak value of about 500 oersteds. Effects of heat treatment, up to 600 C, on directions of magnetization are compared with the results of a.c. demagnetization. It was found that ten flows contained stable components of magnetization, the directions of which lay approximately along the geomagnetic field axis as found by Stubbs. A Devonian north pole position was thus computed as 121 E, 1 N. By consideration of subsequent geological events in connection with their possible effects on the primary magnetization and together with comparison of data from east and west Scotland, it is concluded that the stable magnetic remanence is primary and therefore Devonian in age. Two apparently valid palaeomagnetic pole positions have been established for the Devonian Period, referred to as DI and DII by Creer (1963). Pole DI, 159 E, 30' N, represents an axis of magnetization determined solely from a study of sandstones and evidence for this direction is found in palaeomagnetic surveys from the U.K. (Creer 1957), and from the U.S.S.R. (Kalashnikov 1961; Khramov 1956; Lin'kova 1963 and Vlasov & Kovalenko 1963). That we should consider another pole, DII, for the Devonian period, was originally suggested by Stubbs (1958) after making a palaeomagnetic study of Devonian lavas from Scotland. These lavas of the Midland Valley were found to possess a significantly different direction of magnetization from the sandstones (Fig. I), the corresponding palaeomagnetic pole was situated at 140 E, lo S. Up to this time, laboratory techniques for testing magnetic stability had not been sufficiently developed for general use. However, the arguments used by Stubbs seemed reasonably sound for believing that the DII direction of magnetization was reliable but, as Stubbs pointed out, the results from the Anglo-Welsh cuvette (Creer 1957) and from the Midland Valley both appear valid. Thus from studies made in the U.K. alone, two well-established Devonian pole positions, DI and DII, have been determined. Which of these palaeomagnetic fields represents the true Devonian field ? Or did each field direction exist during the Devonian period? Controlled a.c. and