The space H hyp .4/ is the moduli space of pairs .M; !/, where M is a hyperelliptic Riemann surface of genus 3 and ! is a holomorphic 1-form having only one zero. In this paper, we first show that every surface in H hyp .4/ admits a decomposition into parallelograms and simple cylinders following a unique model. We then show that if this decomposition satisfies some irrational condition, then the GL C .2; R/-orbit of the surface is dense in H hyp .4/; such surfaces are called generic. Using this criterion, we prove that there are generic surfaces in H hyp .4/ with coordinates in any quadratic field, and there are Thurston-Veech surfaces with trace field of degree three over Q which are generic.
51H25; 37B05