The LSH had actually made it's debut in Adventure #247 and soon were guest starring in titles all across the DC line. However it was not until Adventure #300 that The Legion got it's own title! The LSH would be the lead feature in Adventure for over 80 issues!
I have been tacking on issues from this run for a few years now and it is always fun to see the great Curt Swan covers!
As always please feel free to send scans from YOUR collection to firstname.lastname@example.org and I will include them in future galleries!