filing away a particularly entertaining expression that she planned to make sister philomene explain to her - sister philomene was a little older than joan , but painfully shy and with such delicate skin that she blushed like an apple at the least excuse - she followed sister george and sister mathilde through the fishmongers ' section , where sister george bargained shrewdly for a great quantity of sand dabs , scallops , tiny grey translucent shrimp , and an enormous sea-salmon , the pale spring light shifting through its scales in colours that faded so subtly from pink to blue to silver and back that some of them had no name at all - so beautiful even in its death that it made joan catch her breath with joy at the wonder of creation .