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Bistatic-radar scattering from medium- to long-wavelength (80 to 200 meters) ocean waves has been observed with the use of loran A (1.85 megahertz) transmissions and a receiver located 280 kilometers away. The received echoes have been converted into a time-delay, Doppler-frequency map in which the effects of anisotropies in the ocean-wave spectra are clearly shown. The distribution of the echoes in delay-Doppler space is consistent with Bragg scattering from trains of dispersed ocean waves.

Ten-meter radar observations of the sea have been used to study second-order interactions between waves in electromagnetic scattering from the sea. Techniques of coherent, pulsed radar provide echo frequency spectra from several range intervals. The echo spectra are resolved with an analysis window of a few millihertz. These spectra show a clear second-order echo continuum which appears as sidebands about the first-order Bragg scattering lines. Up to one-half of the total echo power has been observed in these sidebands. The principal characteristics of these sidebands vary with time, apparently in response to the sea state. The form of the echo spectra is consistent with the results of perturbation theory computations based on Rice's method.

Continuous-wave signals transmitted from Lunar Orbiter I have been received on Earth after they have been reflected from the surface of the moon. The frequency spectrum of the reflected signals is used to locate discrete, heterogeneous, scattering centers on the lunar surface. The scattering centers are probably distinguished from the surrounding terrain by a higher surface reflectivity. Continuous-wave bistatic radar could provide an important new method for the study and mapping of planetary surfaces.

The deoxyribonucleic acid homologies of Mycoplasma laidlawii type A and type B, M. pulmonis (#47 and #63), and M. hominis were determined by membrane methodology. The homology data revealed a difference in genome size between M. laidlawii type A and type B. This difference also held with stringent conditions of annealing (high temperature). Little or negligible homology was shown to exist between the M. laidlawii strains type A and type B and M. pulmonis strains 47 and 63 and M. hominis. M. hominis showed less than 10% homology to the M. pulmonis and M. laidlawii strains. Neither of the M. laidlawii strains showed more than 2% annealing to the M. pulmonis strains. Reaction rate studies are suggested as a means of demonstrating the phylogenetic relationship between the Mycoplasma and other microorganisms.

Acoustic pulses at 85 Hz (4 m) directed vertically into the lower atmosphere have been tracked by a 36.8-MHz (8-m) pulse doppler radar. Signal-to-noise power ratios in excess of 10 dB were obtained to a height of 1.5 km in the initial tests under conditions of calm winds. This technique has the potential of providing temperature soundings of the lower atmosphere for pollution studies and short-range terminal weather forecasts.

Level of competence reached by Bacillus subtilis 168 lysogenic for temperate phage phi 105 was reduced compared to that reached by nonlysogenic cells. This effect was probably related to an alteration of the bacterial surface. Deoxyribonucleic acid extracted from phi 105 lysogenic bacteria was used to transform other lysogenic bacteria. About 25% linkage was found between the bacterial phe-1 marker and prophage marker ts N15. The order of a few prophage markers relative to phe-1 was established in three-factor crosses. The usefulness of this system for a study of the linkage between an integrated prophage genome and that of its host was discussed.