Bouncing Boy (Chuck Taine; first appearance; last chronological appearance in flashback in Adventure Comics #301/2, Page 7 panel 1 through page 9, panel 4; then pages 1 through 8 in this issue, followed by flashback in Adventure Comics #301/2 Page 9, panels 5-6, then this issue Pages 9 through 10; next in flashback in Adventure Comics #301/2 Page 10, panel 2 through page 13, panel 1)

Brainiac 5 (Querl Dox; first appearance; last chronological appearance in flashback in Legion of Super-Heroes Vol. 3 #39; then in this issue, Page 1 through page 8, panel 5, then in flashback in Secrets of the Legion of Super-Heroes #2 Page 2, panel 5, then in this issue Pages 9 through 10; next in flashback in Adventure Comics #290)

Chameleon Boy (Reep Daggle; behind the scenes; last in flashback in Adventure Comics #282; next in flashback in Adventure Comics #301/2, Page 9, panel 5)

Cosmic Boy (Rokk Krinn; last in flashback in Adventure Comics #282; appears in this issue, Page 1 through page 8, panel 5, then in Secrets of the Legion of Super-Heroes #2 as a flashback; Page 2, panel 5, then this issue, Page 8, panel 6, then in flashback in Adventure Comics #301/2, Page 9, panels 5-6, then in this issue Page 9, panels 1-2, then again as a flashback in Secrets of the Legion of Super-Heroes #2 Page 2, panel 6, then in this issue Page 9, panels 3 through page 10; next in flashback in Adventure Comics #301/2 Page 10, panel 6)

Lightning Lad (Garth Ranzz; last in flashback in Adventure Comics #301/2 Page 9, panel 4; then in this issue Page 1 through page 8; then in flashback in Adventure Comics Page 9, panels 5-6, then in flashback in Secrets of the Legion of Super-Heroes #2, Page 2, panel 6; then in this issue, Page 9, panels 3 through page 10; next in Adventure Comics #290)

Phantom Girl (Tinya Wazzo; first appearance; last chronological appearance in flashback in Legion of Super-Heroes Vol. 3 #39; next in flashback in Adventure Comics #290)

Saturn Girl (Imra Ardeen; last in flashback in Adventure Comics #282, then in this issue Page 1 through 8, then flashback in Adventure Comics #301/2 Page 9, panels 5-6; then in this issue Page 9, panels 1-2 then in flashback in Secrets of the Legion of Super-Heroes #2 Page 2, panel 6, then in this issue, Page 9, panels 3 through page 10; next in flashback in Adventure Comics #301/2 Page 10, panel 6]

Shrinking Violet (Salu Digby; first appearance; last chronological appearance in flashback in Legion of Super-Heroes Vol. 3 #39; next behind the scenes in Adventure Comics #247)

Sun Boy (Dirk Morgna; first appearance; last chronological appearance in flashback in Legion of Super-Heroes Vol. 4 #28; next in Adventure Comics #290)

Triplicate Girl (Luornu Durgo; first appearance; last chronological appearance in behind the scenes flashback in Adventure Comics #282; next behind the scenes in Adventure Comics #247)

Supporting Character(s):

Jerro (in between Action Comics #270/2 and #278/2)

Lori Lemaris (in between Superman's Pal Jimmy Olsen #52/3 and #53/2)

Villain(s):

Brainiac (in flashback to a yet-to-be told tale; last in ???)

Koko (in flashback to a yet-to-be told tale; last in ???)

Guest Appearance(s):

Superman (in flashback to a yet-to-be told tale; last/next in ???)

Location(s):

Midvale

Metropolis (in the 30th Century)

Legion Headquarters

Story Reprinted in:

Superboy Vol. 1 #147/4 (May-June 1968)

Adventure Comics #493 (November 1982)

Legion of Super-Heroes Archives #1 (1991)

Superboy #147 May-June 1968 Replica Edition ([January] 2003)

Supergirl Archives #2 ([December] 2003)

Showcase Presents: Legion of Super-Heroes #1 ([April] 2007)

Showcase Presents: Supergirl #1 ([November] 2007)

Supergirl: The Silver Age Omnibus #1 ([June] 2016)

Supergirl: The Silver Age #1 (2017)

Legion of Super-Heroes: The Silver Age Omnibus #1 (2017)

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