Reverse Shell Stitch

Can anybody help me?? I started to crochet a reversible shell afghan, and row 3 says to do a reverse shell as follows....(insert hook from back to front to back around post of st indicated, draw loop through) 7 times: yo and draw through 8 loops on hook. I have tried reading it over and over, and trying to do it, but it just don't work, or I am just not understanding it. I tried to look the stitch up on the internet, and have had no luck there either. Could it be called something else?? It is a pattern out of the red heart super saver book, Pattern #J27.0004-7C.

Any help would greatly be appreciated.