This issue has variants.
Published before Zap Comix #0. First print is marked in indicia "© November 1967 By R. Crumb" and "Printed by Charles Plymell" in small print on the back cover. Actually released in February 1968.
The on-sale date is the publication date reported in the U. S. Copyright Office filing.
Underground Comix are known for using different prices, covers (art or color variations) and/or interior content to distinguish between printings.
1st print has 0.25 USD cover and is dated November 1967, but actually released in February 1968.
2nd print has 0.35 USD cover. Says 'Printed by Don Donahue' in blue on back cover.
Subsequent printings have four additional pages not included in this original edition.
The Print Mint-
3rd print has 0.35 USD cover. No printer name on back cover.
4th print has 0.50 USD cover. 5th print has 0.60 USD cover. 6th print has 0.75 USD cover.
The Print Mint & Last Gasp-
7th print has 1.50 USD cover.
8th print has 2.50 USD cover. 9th print has 2.95 USD cover.
Sequence on inside front cover.
First published appearance of the "Keep On Truckin" image.
Satire on before/after type ads on back cover of issue.