The authors thank Messrs. J. Charlton, E. Tilman, and N. Geveke
for engineering support, Mr. O.J. Scullen for microbiological support,
and Mr. J. Sites for photographing the cross-section of the egg
(all of the USDA-ARS, Wyndmoor, PA). They also wish to thank Mr.
E. Tilman for reviewing the manuscript.