New tables of Behrens' test of significance

The Tables for using Behren's test of significance of the difference between the means of two Normal samples are already available to reasonable accuracy for all cases save those involving very small samples (Statistical Tables, Tables VI, V2). In some experimental work, however, such small samples occur in conditions in which only Behren's test is appropriate. The calculation of values for such cases is greatly facilitated by the explicit expressions developed in this note for the probability integral, when the numbers of degrees of freedom are both odd.