convert-ly usage question

[Simon Albrecht]

Hello,

this is actually the first time I try to use convert-ly from the 
command-line to update a bunch of files, yet I’m not quite getting there.
I have this in my ~/.bashrc file:
# use current convert-ly
alias convert-ly='/home/simon/lilypond/2.19.47/bin/convert-ly'
and this is what I get:

$ convert-ly -e *.ly
convert-ly (GNU LilyPond) 2.19.47

convert-ly: error: *.ly: Unable to open file
convert-ly: warning: There was 1 error.

Am I overlooking something silly right now?

Best, Simon