Whilst at first sight a comparison chart in black and white may seem a little odd, it is born from the fact that many people are confused by the fact that immature male Bluets are not yet blue, being either beige or greyish in colour. The black patterning is, however, formed and identifiable. This chart encourages concentration on that.
Again, this is males only.
Click on this diagram if you need to open a larger version.