The email listserve is constructed at the start of the semester from the record of those registered for the class.  If you were not squared away in this course with the regisrar at the time that list was constructed, you will not be on that list and you must be added manually.  Email Steven.Manly@rochester.edu and tell your professor that you need to be added to the class email listserve.   Provide him with your email address.