[en] A clinal variation related to the temperature is described in Salpa fusiformis (P.G.), the oriental populations being lesser rich in muscular fibres, but looking more homogeneous than the occidental ones. No similar variation was observed in Thalia democratica (P.S.) although a slight decrease of the fibres mean was detectable during the course of the year in both sectors. Thalia orientalis has been caught in several spots of the oriental sector.
