Study 1 (N = 205) reveals that witnesses often provide vague descriptions. Witnesses leave out information such as sex and race that they certainly noticed (default values). Study 2 (N = 89) weakly supports the claim (Luus & Wells, 1991) that correct identification rates from lineups are enhanced by selecting foils who fit the description of the criminal rather than foils who are highly similar to the suspect. Study 3 (N = 210) indicates that false identification rates can be inflated by selecting lineup foils who fit vague descriptions of the criminal but otherwise differ from the suspect on default values.

The authors examined the use of mug shots as an investigative tool. Data are reported from 3 staged-crime experiments (N = 365) exploring the effects on mug-shot selections of number of faces seen before the confederate criminal's, of biased procedures, and of sorting pictures to fit the description of the criminal. The confederate was frequently selected from mug shots, and few innocent people were selected. Selections of faces declined with number of pictures viewed before the confederate's. Biased instructions and clothing bias increased choices of innocent people but not of guilty people. More innocent faces were selected when the pictures matched the confederate's description than when the pictures were not sorted to match the confederate's description. Viewing mug shots had no effect on subsequent identifications in lineups. Implications for police use of mug shots are discussed.

A combined scanning Auger, XPS, scanning SIMS, and TEM (electron diffraction) investigation of naturally‐occurring goethite surfaces in contact with 10−3 M KH2PO4 solution for 90 d at 60 °C has shown that isolated crystallites of the mineral griphite, Fe3Mn2(PO4)2.5(OH)2, are formed by reprecipitation from solution. No adsorbed phosphate can be detected on the goethite surface above 0.1 atomic % and there is no phosphate penetration of the goethite crystals. Evidence concerning initial adsorption of phosphate, before recrystallization, is reconsidered. The results suggest that phosphate retention in Fe oxide systems may be due primarily to precipitation rather than adsorption.

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The kinetics of the hexagonal-cubic phase transformation of zinc sulfide have been studied in vacuo, in zinc vapor, and in sulfur vapor in the temperature range 800-900 "C by a powder X-ray diffraction technique. The transformation rate is enhanced in the presence of sulfur and zinc vapor. In vacuo and in sulfur vapor the reaction is nucleation-controlled with activation energies of 95.0 and 98.5 + 5 kcal, respectively. In zinc vapor the reaction is diffusion-controlled with the diffusion coefficient expressed asThe modes of catalytic action by sulfur and zinc vapor on the solid phase transformation reaction are discussed. Canadian Journal of Chemistry, 46, 2881 (1968) IIntroduction Experimental Our interest in the phase transformation of zinc sulfide stems from observations on sintering studies of ZnS powder (1) which indicated that the wurtzite-sphalerite transformation rate was enhanced by ambient vapors, viz. Zn and sulfur. This catalytic effect of a gas on a solid state reaction, while not a new one, appealed to us as a promising method for probing the nature of gas-solid interactions, especially the effect of an adsorbed species on the solid rather than the common inverse effect. Two modes of this catalytic action were visualized with their origins: (a) on the surface, where the most probable mode of action might be nucleation and (b) in the interior, where the action must involve solubility with subsequent transport or mobility steps. With regard to the latter mode, if the catalytic action is not entirely restricted to the surface, the Zn and sulfur vapor species possess a useful intrinsic parameter in their large relative difference in diameter, i.e. rs,/r,, --2.'Present address: Kinetics Research Group of Hungarian Academy of Sciences, Szeged, Hungary.2To whom correspondence on this paper should be addressed. 3Present address: Chemistry Department, Immaculata College, Immaculata, Pa. 4Present address: Chemistry Department, University of Western Ontario, London, Ontario.The ZnS powder used in this work was from two batches of BDH laboratory reagent, I and 11. In both cases, the X-ray diffractograrns showed (2) peak intensities characteristic of 80% wurtzite-20% sphalerite mixture. The particle radius of the powder is calculated to be 6.1 x cm from nitrogen adsorption measurements (3).The sulfide samples (ca. 200 mg) were annealed in a static system in vacuo or with sufficient zinc or sulfur to give the requisite pressure. The reaction chamber consisted of a quartz vessel of the design already described (4). After the anneal in the furnace at the appropriate temperature (4) and the removal of the powder from the quartz vessel, the sample was weighed, crushed in a mortar, and analyzed using a Norelco diffractometer model X-86.The extent of reaction was determined by a method similar to that used by Edwards and Lipson (5). This method assumes that the intensity of the (111) face of the cubic structure increases at the expense of the (100) and (101) planes of the hexagonal structure. The fact that the (002) ...