I think you've picked up the theme this week: The Bengals are (have) working (worked) out several players this week, mostly linemen and receivers. Ranging from two centers in Justin Hartwig and Eric Ghiaciuc, to Dexter Jackson and Eron Riley.
However, the invitation for receivers didn't stop there.
The Bengals also worked out London Crawford and Kole Heckendorf this week.
Crawford, a former Arkansas Razorback, recorded 53 receptions for 747 yards receiving in his career. His junior year, Crawford recorded career highs in receptions (27) and yards receiving (311). This is his first year out of college football.
Heckendorf, formerly of North Dakota State, was originally signed as an undrafted college free agent by the Green Bay Packers. After being released during the preseason, the Detroit Lions signed him to their practice squad in mid-October. After being cut by the Lions in May this year, the Seattle Seahawks signed him, but releasing him in late August. Heckendorf started 42 of 43 career games, recording 178 receptions for 2,732 yards receiving and 17 touchdowns.