Within a Budding Grove (vol II pp 634-51)

Saint-Loup engaged to a Mlle d’Ambresac? (634). Albertine (635). Andrée (636). Gisèle (637). Days with the girls (643). Françoise’s temper (649). Balbec through Elstir’s eyes (651).

p 637 | Giotto's Idolatry.

         | Diabolo
...I was taking a short stroll with Albertine, whom I had found on the beach tossing up and catching again on the end of a string a weird object which gave her a look of Giotto's 'Idolatry'; it was called, as it happened, a 'Diabolo,' and has so fallen into disuse now that, when they come upon the picture of a girl playing with one, the commentators of future generations will solemnly discuss, as it might in front of the allegorical figures in the Arena Chapel, what it is that she is holding. II 637 

p 640 | Which would you rather have as a friend, Alceste or Philinte? Two characters from The Misanthrope, a 17th-century comedy of manners in verse written by Molière. Alceste: protagonist and "misanthrope," is quick to criticize the flaws of everyone around him, while Philinte is a polite man who recognizes the importance of occasionally veiling one's true opinions in a social context; considered to be Alceste's foil. (Wiki)
p 640 | Le Gaulois : French daily newspaper, founded 1868.
p 643 | ineluctable = inevitable ; atavusm = throwback, reversion to past style
p 644 | inflorescence = floral axis, flower cluster (girls as flowers); Dreyfusism = anti-Semitism (in this context, i.e., going back to the past. Note that Dreyfusards were pro-Dreyfus); clericalism = maintaining power of religious hierarchy ; anterior = preceding ; cryptogamous = member of a formerly recognized taxonomic group that included all seedless plants and plantlike organisms, such as mosses, algae, ferns, and fungi ; papilionaceae = legume, pea, bean family.
p 649 | Gisèle is a slacker!
p 651 | Eulalie is the retired domestic servant in Combray, who visits Aunt Léonie with the Curé and has an ongoing rivalry with Françoise (cf I 41-51).  St. Eloi (Elegius; patron saint of goldsmiths & coin collectors) ; Cimmerians = ancient equestrian nomads of Indo-European origin.