I found two other interesting images to add to the former theme of "tesselation": a hyperbolic quilt (by Helaman Ferguson) and what I, albeit loosely, relate to "the Arctic no longer vicious Circle" reference in Ada, namely "geodesic rectangular coordinates on annular hyperbolic plane.

 

There's Vaniada's death in association to the pressed leaves found in the begining of the novel, and various other clues about VN's explorations of "performing words"and "upside-down metaphors" related to our globe, to infinity and to everlasting time.  As "Van Veen himself was to find out, at the time of his passionate research in terrology (then a branch of psychiatry) even the deepest thinkers, the purest philosophers, Paar of Chose and Zapater of Aardvark, were emotionally divided in their attitude toward the possibility that there existed 'a distortive glass of our distorted glebe' as a scholar who desires to remain unnamed has put it with such euphonic wit." (Ada, or Ardis). 

 

After comparing Van's "Mascodagama" revertible feats with a paragraph in Bend Sinister, highlighted by S.E.Sweeney's reapraisal of an acrobat's "amphiphorical gesture,"* I feel closer to the conclusion that, in V.Nabokov, we are not in the realm of a 'fine excess' and rhetorical hyperboles only, but perhaps confronting (frightened Blaise is, of course, Pascal) mathematical explorations of human limitations in relation to time/space expressed by the means of words and structure.

 
Bend Sinister: "... after one backward glance from the first landing ran upstairs trailing her wrap with all its constellation — Cepheus and Cassiopeia in their eternal bliss, and the dazzling tear of Capella, and Polaris the snowflake on the grizzly fur of the Cub, and the swooning galaxies — those mirrors of infinite space qui m'effrayent, Blaise, as they did you, and where Olga is not, but where mythology stretches strong circus nets, lest thought, in its ill-fitting tights, should break its old neck instead of rebouncing with a hep and a hop — hopping down again into this urine-soaked dust to take that short run with the half pirouette in the middle and display the extreme simplicity of heaven in the acrobat's amphiphorical gesture, the candidly open hands that start a brief shower of applause while he walks backwards and then, reverting to virile manners, catches the little blue handkerchief..."

 

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* - "In referring to Nabokov’s metaphorical constructions, Susan Elizabeth Sweeney uses the term “amphiphore” (Sweeney 1987). The “amphiphore” is a “portmanteu word” borrowed from Bend Sinister. It highlights the capacity of a metaphor to activate different, often contradictory referential frames. The metaphorical entity “letters-butterflies” from Speak, Memory (p.251) serves as an example of the “amphiphoric gesture” (p.133) [  ] the amphiphore embraces the past, present and future tenses by indicating what is anticipated as the “future recollection” within the actual perception.
The Models of Space, Time and Vision in V. Nabokov’s Fiction: Narrative Strategies and Cultural Frames: Marina Grishakova
https://www.google.com.br/?gws_rd=cr#q=susan+sweeney+bend+sinister+amphiforichttps://www.google.com.br/?gws_rd=cr#q=susan+sweeney+bend+sinister+amphiforic