Mac Mail fonts

I am using Arial size 12 for my writing font in Mac Mail, but when I recieve replies back, my font that I typed out below the responders email is in Times New Roman and not Arial, and I am wondering if it is displaying at their end as Times New Roman?

My signature is also in Arial, and always comes back as Arial, but the main message font itself is always in Times New Roman.

See below:



Any ideas?

Thanks
Liam

I think I had this problem before as well. Try changing the message format to plain text (preferences > composing) and trying a few test messages.