Both the mesoscopic structure (as seen by small angle neutron scattering (SANS)) and the dynamics (as seen by neutron spin echo (NSE) technique) of the critical fluctuations were measured in C2D6 close to the liquid–gas phase transition. These experimental data complete previous results obtained with CO2. SANS results allow a precise determination of the critical exponents ν and η, and of the universal static scaling function g(x). Correspondingly, NSE data give access to both the critical dynamic exponent z and the dynamic scaling function Ω(x). Our results evidence the limitations of the Kawasaki model.