Two new pyrrolizidine alkaloids, 7-0-acetyl-9-0-latifolylretroneine [1] and 9-0-latifolylretroneine [2], were isolated from Hackelia californica after Zn reduction. The alkaloids are analogues of latifoline, which was previously found in Hackelia floribunda. Neither of the new pyrrolizidines could be isolated prior to Zn reduction; hence they were presumed to be present in the plant as N-oxides. Female Gnophaela latipennis moths and larvae raised on their natural host plant, H. californica, contained an alkaloid which was different from the plant isolates. Spectral evidence showed that this alkaloid was callimorphine, 9-0-(2-acetoxy-2-methyl) butanoylretronecine, a pyrrolizidine reported earlier from other moth pyrrolizidine alkaloid specialists, but not from their host plants. Callimorphine was also found in wild-caught Gnophaela minulata (host plant unknown).