This issue has variants.
Indicia title is "ATLANTIS, THE LOST CONTINENT, No. 1188." Code number is ATLANTIS O.S. #1188-615. Copyright 1961 by Metro-Goldwyn-Mayer, Inc. Adapted from the movie "Atlantis, the Lost Continent." This edition has 2.25 pages of ads and 3 pages of promos that replace material in the non-ad edition. There is also a "Prizes - Prizes - Prizes! Announcing Big Dell Comics Contest!" banner across the middle of the cover that is not on the non-ad cover.
Inside front cover; black and white. Five photos from the movie and a partial cast list.
This original version of this story in the non-ad edition is 32 pages. In this version, page 3 is deleted. Panels 1, 2, 4, and 6 are deleted from page 15. Panels 1-5 on page 16 are deleted. Panel 1 on page 17 is deleted and panel four is highly cropped and a thought balloon is deleted. Panels 1 and 3 on page 18 are deleted and panel 2 is cropped. The net result is the original four page centerfold now takes up two pages of story with the two-page centerfold being a promo for the Dell Trading Post. Panels on the last page are all cropped to allow for a 1/4 page ad.
This promo comes after page two of the story. Promo for 3000-prize Dell Comics Contest. First prize is a jet plane trip for four to Hollywood with visits to TV and movie studios and Disneyland. Entry is two cover logos from Dell comics. This ad replaces page 3 of the story of the non-ad edition.
Centerfold. Promo for Dell Trading Post. Premiums available for clipped title strips from covers of Dell comics. This promo comes in the middle of the story.
Inside back cover; color. Ad for Kool-Aid soft drink mix featuring an "identify the animals" contest. Contest rules are on the bottom of the last interior page. This ad replaces "Myth and Mystery" of the non-ad edition.
Back cover. Ad for Twinkles breakfast cereal featuring the characters from the Twinkles storybook packages. Premium is a 45 rpm record of Twinkles stories on one side and songs from the NBC cartoon series "King Leonardo and his Short Subjects" on the other for 25 cents and two box tops. This ad replaces "The Anatomy of a Volcano" of the non-ad version.