. : tt lntetetan hn anaced ah VE eee Pals (FOIb) shows : : abe aba of Ps absorption lines of References and Notes Summary Already beyond doubt that O and BO super- lengths in §, ¢, and ¢ Orionis. During four Aerobee flights Stecher (20) has scanned the spectra of at atmospheres. The spectrum 8, T. A. Chubb and E, T, Byram, Astrophys. J. 138, 617 (1963); E. T. Byram, T. A. Chubb, M. W. Werner, Ann. Astrophys. 28, 594 (1965), while in Sirius (A1V) the main feature is the Mg II resonance doublet. On 20 September 1966 Jenkins and Morton (79) flew an all-reflective //2 spectrograph on an Aerobee rocket, and obtained spectra of eight stars in Orion with about 1-A resolution. These photographs confirmed the earlier results of the wavelength shifts in the C IV and Si IV absorption lines and the unexpectedly weak interstellar Lyman-q lines. The wavelength range least ten hot stars with 5- and 10-A resolution longward of 1100 A. He also has found the C IV and Si IV resonance lines to be in emission with ab- sorption components to shorter wavelengths in some of the stars. On an Aerobee launched on 16 March 1967 Carruthers (27) used a windowless image intensifier to photograph spectra of some 12 stars from 1030 to 1400 A with 2- to 3-A resolution. He con- firmed the shifts of some of these lines in £ Orionis and found the same phenomenon in ¢ Puppis, y Velae, and « and « Orionis. Both the spectral data and photon counters lead him to suggest that the photon flux decreases shortward of 1150 A even in the hottest stars. According to theories of model stellar atmospheres only stars of spectral types from O to about B3 may be expected to be bright in the ultravioletwavelength region. Observations of the strong resonance lines between 911.6 and 1900 A will yield new information permitting construction of better models for the outermost layers of OB stars. However, an adequate theory of line-formation, including non-l.t.e. effects, should be used if an accurate physical representation it has been is to result. demonstrated giants are surrounded by expanding between 1900 and 3000 A is formed chiefly in the same layers of the star as is the part of the spectrum observed with groundbased equipment; consequently, groundbased observations can be used to establish an adequate model. With such a model, observations of the absorption lines due to the first and second ions of the metals should permit new and reliable determinations of the abundances of Fe, Cr, Mn, and Ti in B stars. The photometric and the spectral observations so far available of O and B stars do not generally conflict seriously with the predictions of theory, provided that we use line-blanketed models for the comparison and that we correct for the effects of interstellar reddening when necessary. =a was extended to 1130 A and revealed absorption lines of N V, Si III, and C Ialso shifted to shorter wave- 1, A. B. Underhill, Publ, Dominion Astrophys. Obs. Victoria, B.C. 11 433, 467 (1962). 2, The flux F, per unit wavelength, which is more relevant to observational procedures, is cFy/\*; F, in the ultraviolet probably exceeds that in the visible for types even later than B4. 3. D. M. Mihalas and D. C. Morton, Astrophys. J, 142, 253 (1965); C. Guillaume, Bull. Astron, Inst. Neth, 18, 175 (1966). In the first paper the detailed shape of the strong ultraviolet-absorption lines is taken into account: in the second, the line profiles are represented by rectangles. 4. D. C. Morton, Astrophys. J. 139, 1383 (1964); 141, 73 (1965), 5. C. Guillaume, W. van Rensbergen, A. B. Underhill, Buil. Astron. Inst. Neth. 18, 106 (1965); C. Guillaume, ibid.. p. 175 (1966). . E. W. Elst, fbid, 19, 90 (1966). . E, T. Byram, T. A. Chubb, H. Friedman, J. E. Kupperian, Astron. J. 62, 9 (1957); J. E. Kupperian, A. E. Boggess, J. E, Milligan, Astrophys. J, 128, 453 (1958); E. T. Byram, T. A. Chubb, H. Friedman, ibid. 139, 1135 Mg I, Mg HU, Si I, Fe I, and Fe II beiow the earth’s atmospheric cutoff, (1964). 9, A. M. Smith, Astrophys. J. 147, 158 (1967). 10. J. D. Alexander, P. J, Bowen, M. J. Gross, D. W. O. Heddle, Proc. Roy. Soc. Ser, A 279, 510 (1964). 11. I. S. Gulledge and D. M. Packer, Astron. J. 68, 537 (1963); personal communication. 12, A. E. Boggess, Ann, Astrophys. 27, 805 (1964); A. E. Boggess and J. Borgman. Astrophys. J. 140, 1636 (1964). 13. R. D. Bless, A. D. Code, T. E. Houck, J. F. McNall, D. J. Taylor, Astron. J. 70, 667 (1965). 14. T. P. Stecher and J. E. Milligan, Astrophys, J. 136, 1 (1962); T. P. Stecher, Astron. J. 70, 643 (1965); Astrophys, J, 142, 1683 (1965). 15. D. C. Morton and L. Spitzer, Astrophys. J. 144, 1 (1966}; D. C. Morton, ibid. 147, 1017 (1967). 16. M. E. Stone and D. C. Morton, ibid. 149, 29 (1967). 17. R. Wilson, Publ. Roy. Obs. Edinburgh 2, 61 (1958), 18. K. G. Henize, L. R. Wackerling, F. G. O’Callaghan, Science 155, 1407 (1967). 19. E. B. Jenkins and D. C. Morton, Sky and Telescope 33, 162 (1967); Nature 215, 1257 (1967}. 20. T. P. Stecher, paper presented at Yerkes meeting of Amer. Astron. Soc., 1967. 21. G. R. Carruthers, Astrophys. J. 148, L141 (1967); ibid., in press. (6), Delgado (7), MacLean (8), and others are significant in this connection. On the other hand,it is surprising that Causality, Consciousness, and Cerebral Organization the physiologists show some reluctance to teach psychological concepts. More than a minimum knowledge of the relationship between brain and psychological function is essential for students in biclogy and medicine, both because Walter R. Hess Psychology has been largely, if not exclusively, regarded as being in the domain of philosophy, and, until recently, reference to the brain as the substrate of psychological function was infrequent. It should be admitted that regional differences of approach exist; for example. in the United States psy§ DECEMBER 1967 chological concepts are influenced more by the natural sciences than they are in tradition-bound Europe. The works of Herrick (/), Lashley (2), and Hebb (3), the publications of the experimentally oriented Canadian neurosurgeon Wilder Penfield (4), and more recent noteworthy works of Kliiver (5), Ploog this function plays a role in the biology of men and the other higher mammals and because such knowledge is necessary for an understanding of mental illness. For all these reasons, an ef- fort to survey psychological problems in biological perspective seems justified. If a series of events relating to our past experience comes to our attention, we feel compelled to look for a causal ~ . The author is professor emeritus of physfology, University of Ziirich. Ziirich. Switzeyland: 1779