An experiment was undertaken to study the effect of exposing incubating embryos to short ultrasonic pulses across the intact egg shell. Three minute exposures to 2.25 MHz. pulses, average incident intensity equals 28.6 mW./cm.2, failed to show any effect on embryonic mutation, hatchability, sex ratio, or body weight. On the average the ultrasonic absorption of the egg shells ranged from 26 dB./mm. at 0.6 MHz. to 100 dB./mm. at 2.25 MHz. The transmitted power incident on the blastodisc, consisting mainly of spectrum components below 1.0 MHz., was estimated at congruent to 1% of the incident power.