I have seen the same reference, and I think I have seen it more than once.
I am reasonably certain the reference was to temperatures below 70 F, during
metamorphism.  Should such exposure take place, I think that her subsequent
fertility will be severely damaged.
Lloyd
Lloyd Spear, Owner of Ross Rounds, manufacturer of comb honey equipment
for beekeepers and Sundance pollen traps.
http://www.rossrounds.com
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