Abstract
Observations made on several hundred adult male spiders of two species of Araneus indicate a highly significant correlation (p<0.001) between the length of a segment (tibia of the second leg) and the number of macrosetae (“spines”) present on the segment. This result is further supported by observations on the first tibiae of about twenty male A. trifolfum, one of the two species, and by a few observations on immatures of the two species. A short summary of the methods used in taking the measurements and making the calculations is followed by discussion of the implications of this correlation with reference to species determination and geographic variation