A direct test for the survival of gaseous nuclei in vivo.

It has recently been demonstrated that bubble formation in the crab Pachygrapsus crassipes is induced by limb motions following decompression from nitrogen pressures as low as 2 atm. Preformed gaseous nuclei are not involved in this process and are absent from this animal. We further demonstrate here that nuclei do not remain in the body fluids when the motion-induced bubbles dissolve. This shows that gas phases do not become protected against dissolution in vivo as has been proposed by other workers. This may have important implications concerning the origin of bubbles causing decompression sickness in higher animals.