294 
Psyche 
[December 
sample, Abalos and Baez also observed this fact because they noted 
that the red irregular square stretched . . almost to the spinnerets”. 
A more conspicuous feature was the presence of a circular black spot 
in the center of the square. The presence of a round black spot, 
centered in a reddish yellow irregular square, was sufficient to dis- 
tinguish specimens of population No. 2 from all other specimens. 
Any attempt to characterize the faded yellow patterns observed in 
populations Nos. 3 and 4 becomes hazardous. No two patterns were 
alike in either of the two populations. The majority of the specimens 
from No. 3 had patterns similar to those illustrated in Figures 11 
and 12. The pattern edges were less distinct than those seen in Nos. 
1 and 2. It is interesting to note that when McCrone and Levi 
(1966, p. 182) state “. . . the use of color pattern as a diagnostic 
species character must be done with great caution”, they were prob- 
ably studying the Peruvian counterpart of population No. 3. This 
variability is equally true of population No. 4, of which only four 
specimens were available for study. All four patterns are illustrated 
(Fig. 16 through 19). More specimens need to be studied before 
one can be reasonably certain that the yellow markings were restricted 
to the anterior portion of the venter. 
Color. The pattern colors of Nos. 1, 3 and 4 varied from dull to 
brilliant yellow, while those of No. 2 varied from dark red to 
reddish-yellow. But the colors of the preservatives were of more in- 
terest to me than the colors of the patterns. It was obvious that the 
preservative for No. 2 was tinted with a red pigment and the 
preservatives for Nos. 1, 3 and 4 were colorless. Using the technique 
described earlier, the absorption curves of the preservatives of Nos. 1, 
2 and 3 were measured and plotted and a comparison of the curves 
in Figure 20 shows the dramatic difference between the undiluted 
samples (see unbroken curve in Fig. 20). Following a 4:1 dilution 
of the solution from population No. 2 (lowest curve), the spectral 
curve (dotted line) moved into the absorption range of the other 
samples. Undoubtedly, the same pigments are present in all three 
populations. In comparison with No. 3, one might suggest that the 
greater amount of dissolved pigments in No. 2 resulted from the 
larger pattern in No. 2. But it might be possible that the red and 
yellow pigments (non-melanins) are not necessarily limited to the 
pattern areas and are present in the black (melanin) pigmented areas 
as well. This argument becomes less important when comparing 
No. 1 to No. 2. Indeed, the area covered by the shield (No. 1 ) is 
greater than that of the square (No. 2). Therefore, the greater in- 
