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A 6 A resolution electron density map of pig muscle phosphoglucose isomerase has been obtained. From this map it has been possible to isolate a single molecule and to assign tentative subunit boundaries. The binding of the competitive inhibitor 6-phosphogluconate has been studied. The binding site appears to be close to the subunit interface.

The task used was designed to force Ss consistently to process the letters of a tachistoscopic display in the same spatial order, if Ss are able to process the letters in a brief display serially and if Ss have enough voluntary control over the selection of a processing order to use the order chosen by the E. In the main series of experiments the set of slides shown in each session included slides having a blank space in some position in the linear array of letters. For control, no-blank slides, a sharp, monotonic decrease in the percentage of correct detections of a signal letter with distance of the signal letter from the focusing dot was obtained. An unexpected result from the slides having a blank space was that detection of the signal letter was considerably more accurate on the slides having a blank space immediately following the signal letter than on the control slides having no blank space or the slides having a blank space immediately before the signal letter in the processing order. In one experiment blank spaces were replaced by black rectangles with no substantial change in the pattern of results. The results from the slides having a blank space or a black rectangle were interpreted as indicating that the onset of processing the image of a letter was determined by the distance in the display from the focusing dot to the letter and that the duration of processing an image of a letter was determined by the distance in the display from the letter to the next letter in the processing order.

Ss were instructed to “read” displays of letters presented for several milliseconds and to indicate which of three signal letters had been present. The instructed reading path through the display was manipulated by assigning point values to display locations. The results indicated that the letters simultaneously presented were at some stage successively processed. It was suggested that the serial operation was a successive preservation of locations in an image of the display by means of a series of tests of category descriptions on each image location.

Solid bars or blank spaces placed before, after, or on both sides of a pronounceable four-letter string embedded in a longer string of letters facilitated recognition of the embedded string. This effect was equal whether bar or blanks were used, and whether the embedded string was a word or a pronounceable nonword. The effect of bars or blanks on pronounceable strings was interpreted in terms of a multiletter processing operation.

T K K he agitation for teaching reform which has followed the student disturbances of the past few years bears the credentials of a long and respectable university tradition of bettering the lot of students. The youthfulness of many of the faculty reformers, however, and their consuming dissatisfaction with their own teaching performances, suggest that this movement has more to do with the needs of the junior faculty themselves than those of the students. When those needs are translated into teaching practice, they express themselves in an encounter group or group therapy atmosphere that bears little educational utility beyond exorcizing part of the young professor's guilt at having so recently joined the "Establishment." The young reformer's indictment of himself, one understands, is meant to stand as an indictment of the entire system, and the reader is expected to admire the confessant for his candor rather than to

sensus in its favor. In the university reform commands the nominal support of teachers, students, and administrators, equally: that is to say it is supported both by the reformers and by those who are to be reformed. As with the ecology issue, no opponents are visible. The word "reform" has become a slogan, believed in seriously perhaps only by liberal professors who will be called on to sacrifice