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Psyche 
[Vol. 93 
included in the data. The more complete data of this study suggested 
interpretational changes at two loci from those reported by Turan- 
chik and Kane (1979). The present data show that the ALP bands 
are properly interpreted as a single variable locus rather than as two 
separate loci. Also, we have chosen a more conservative interpreta- 
tion of the XDH data. Electrophoretic analysis of XDH in N. tell- 
kampfi populations produces a single band per beetle with slight 
differences in mobility between some individuals. Initially these data 
appeared to be consistent with data reported by Singh et al. (1976) 
for a variable XDH locus in Drosophila pseudoobscura. However, 
application of additional techniques which Singh et al. (1976) used 
to reveal multiple bands in D. pseudoobscura heterozygotes, failed 
to reveal any multiple banded N. tellkampfi individuals at the XDH 
locus. More recently, Finnerty and Johnson (1979) have shown that 
data such as these may be the result of post-translational modifica- 
tion of an enzyme encoded by a monomorphic locus. We have 
chosen this interpretation of the XDH locus in the present study. 
PGM was not assayed in previous studies of N. tellkampfi (Giuseffi 
et al., 1978; Turanchik and Kane, 1979) and therefore populations 
of N. t. tellkampfi were re-collected and surveyed for this enzyme. 
The majority of the data analysis was accomplished using a Fortran 
77 version of the BIOSYS-1 program developed by Swofford and 
Selander (1981). 
Results 
Of the nine putative genetic loci examined in this study, five were 
polymorphic and the remaining four were monomorphic with the 
same variant fixed in all populations of the four taxa (Table 1). 
Genetic variability in N. tellkampfi populations has been estimated 
as the proportion of polymorphic loci per population (P) and the 
average frequency of heterozygous loci per individual (H) (Table 2). 
The average N. tellkampfi population is polymorphic at approxi- 
mately 30% of its loci and the average individual in such a popula- 
tion is heterozygous at 9.4% of its loci (Table 2). These values are 
somewhat lower than those reported previously by Turanchik and 
Kane (1979) as a result of the addition of another invariant locus 
(PGM) and the more conservative interpretation of the XDH locus. 
However, these values of P and H still approach values typically 
reported for many surface invertebrates (Selander, 1976). Therefore, 
