Using D. L. Kendall's paper as a base of reference [Geoscience Abstracts 2-3090], the various discrepancies in current thinking about the Pb-Zn ore genesis problem are pointed out. Two major problems are described as critical. 1) "How, if mobilized, can such variably chemically reactive elements as Zn, Pb, Ba, and F be moved in quantity in solutions that are essentially either connate. . . or meteoritic?" 2) "How [to] distinguish metasomatic replacement of such features as 1) possible lime-secreting algae or bacteria later replaced by sulfides. . from 2) primarily biologically precipitated sulfides?" Discussion of the 2 points leads to the final statement that "perhaps clear evidence might come from regions of flat-lying, little deformed strata."