In my previous article upon this subject, I treated upon the classification and the particular distinguishing characters of the genus Harpalus ; in this I wish to call attention to their specific differences, by noting those variations of form or structure which are so constant as to cause us to consider them as denoting distinct species. The general form of the beetles of this genus is oblong-oval, rather broad, thorax quadrate, and in length from .30-1 inch, black piceous, shining. Our northern exceptions to this colour are H. viridiræeneus, Beauv., and H. erraticus, Say, the former being bright brassy-green, the latter dark ferruginous or the colour of immaturity.