Statistical treatment of vertebral counts of young herring taken along the southeast coast of Vancouver island demonstrates significant differences between localities in the same year and in the same locality in different years. These differences are probably largely due to the effects of environment. The larger fish in a sample tend to have higher vertebral counts. This increase is somewhat greater in the caudal than in the abdominal region, and is accompanied by a disproportionate increase in mean number of tail vertebrae. Between samples, variation in total count is reflected mainly in the abdominal vertebrae, and significant differences in mean tail count may occur where no difference in total count exists.