PARIS wears her greenest livery and puts on her most gracious airs in early summer. When the National Fete commemorative of the Bastille's fall has gone, there are few Parisians of wealth or leisure who remain in their city. Trouville, Deauville, Etretat and other pleasure cities claim them and even the bourgeoisie hie them to their summer villas.The city is given up to those tourists from America and England whom Paris still persists in calling Les Cooks in memory of that enterprising blazer of cheap trails for the masses. Your true Parisian and the stranger who has stayed within the city's gates to know her well, find themselves wholly out of sympathy with the eager crowds who follow beaten tracks and absorb topographical knowledge from guide-books.