If you click on the button in the top bar that says "forums" it will bring you to a list of categories. You do your best to guess where it belongs, then click on the words. When you click on those words it will bring you the list of posts in that category. Towards the top right of the list there is a button that says "post thread". That will bring you to a new page where you can type up your concern.
It is better to post a new thread, it keeps things clearer, and people are more likely to see it if it has 0 replies.
I am guessing that is just an extra large mineral deposit. If your hens seem healthy I wouldn't worry about it too much, but if you continue to see ones that large I would start a new thread to see if anyone has ideas about why it may be reoccurring.
