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The cover of Jungle Comics #67 appears not to be by the same hand as the others. Online sources suggest that the artist might be Ruben Moreira. Whoever the artist was, however, the proportions and attitude of the male figure strongly suggest that he was a big fan of Burne Hogarth, who implemented in his comics and advocated in his art instruction books an idealized, observation-free method of figure construction that impressionable young artists really ought to avoid like the plague. Hogarth’s single-minded emphasis on concepts and construction ruined his own art; don’t let it ruin yours.
Also, I’m not entirely convinced that Jungle Comics #66 is by Doolin — which is why the file name does not include the name of the artist. The design and inking of the woman’s face suggests to me that the cover might be by a Filipino artist. But maybe it is by Doolin. Who knows?