Ohio State University
Ohio State University: Bryophyta (Mosses)
This general overview of mosses is concise, with good diagrams and illustrations. The text is written at a higher level, but the information to gain is worth taking some time.
Other
Iab: What Is Bryology? A Bryologist?
The International Association of Bryologists gives a short description of bryology, along with descriptions and pictures of the three types of bryophytes: mosses, liverworts, and hornworts. Pictures include the scientific name of each...