hi David,
That's the output I have:
pi@RPi-JMRI:~ $ ls -la /dev/tty[a-z]*
crw-rw---- 1 root dialout 204, 64 Jan 13 22:32 /dev/ttyAMA0
crw------- 1 root root? ? ? 5,? 3 Jan 13 22:32 /dev/ttyprintk
crw-rw---- 1 root dialout? ?4, 64 Jan 13 22:32 /dev/ttyS0
crw-rw---- 1 root dialout 188,? 0 Jan 13 22:33 /dev/ttyUSB0
?