In some fermentations with a Beauveria bassiana strain capable of producing beauverolides A-F, the beauverolide metabolites contain alloisoleucine residues in place of isoleucine and are designated by the subscript a. Beauverolides Ea and Fa are shown to be the cyclotetradepsipeptides cyclo-[3-hydroxy-4-methyloctanoyl-L-valyl-L-phenylalanyl-D-alloisoleucyl] and cyclo-[3-hydroxy-4-methyloctanoyl-L-phenylalanyl-L-phenylalanyl-D-alloisoleucyl] respectively. Beauverolides Ba and Ca are the homologues derived from 3-hydroxy-4-methyldecanoic acid. Beauverolide Ca is identical with isarolide C. The structures of beauverolides A and D are deduced from the mass spectra of the beauverolide mixture. Beauverolide Ba is identical with isarolide A and with beauverilide A. In Part 1, two beauverolides, H and I, isolated from strain UICP 32 of the entomopathogenic fungus Beauveria bassiana (Bals.) Yuill. were shown to be the cyclotetradepsipeptides (1) and (2) respectively containing L-phenylalanine (Phe), D-leucine (Leu), and L-alanine (Ala). In an earlier communication, we reported the isolation of a mixture of some similar compounds from a different strain, UICP 22, of the same organism obtained from a pupa of the Gum Emperor moth, Antheraea eucalypti in New Zealand. In the present paper, consideration of the results of acid hydrolysis and amino-acid analysis, together with high-resolution mass spectrometric (h.r.m.s.) studies, leads us to propose structures for the six components of the mixture, beauverolides A to F. When this mixture was first obtained, amino-acid analysis indicated the presence of isoleucine (Ile) in beauverolides B, C, E, and F. In later work, after some components of the mixture had been separated and purified, it was found that Ile had been replaced by alloisoleucine (aIle). These beauverolides are designated by the subscript a.