288 
Psyche 
[December 
6. The hypothesis that Nephila stabilimenta are vestigial seems to 
be largely untenable. 
7 . We suggest that the devices built into skeleton webs could repre- 
sent a primitive stage of stabilimentum construction. Hypothetical 
steps leading from this stage to the evolution of the perpendicular 
stabilimentum could include one at which zig-zag ‘overstitching’ 
was used to reinforce a line of junction between old and new 
sections of a partially renewed web. The further evolution of 
stabilimenta from this stage could have followed different func- 
tional pathways in different species. 
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