Zeedman on Homegrown Goodness did a 2010 trial of several naked-seeded varieties. He called the o.p. seeds he collected "Little Greenseed".
I think that was also called the Long Island Seed Project.
There is a lot of information on the site - quotes from articles that I could copy here.
For instance: Inheritance of Seedcoat Development and Color
Several inheritance studies conducted in the early 1950s (Heinisch and Ruthenberg 1950; Mudra and Neuman 1952; Schoeniger 1950, 1952, 1955; Weiling and von Becherer 1950) produced conflicting interpretations as to the mode of inheritance of the hull-less condition. More recent work by Stuart (1983) showed convincingly that a single recessive gene conditions the existence of a thin, parchment like seedcoat. At least two additional modifying genes, one of which appears to be dominant (J.B. Loy unpubl.), further reduce the degree of seedcoat development. In seed classified as completely hull-less, the outer seedcoat layers are reduced to the extent that seed take on the appearance of the inner seedcoat layer (chlorenchyma) which is normally dark green (Fig. 1, 2). I have found two color variants of chlorenchyma issue, light green, recessive to dark green, and yellow, recessive to both dark green and light green. When the outer seedcoat is partially developed (monorecessive condition) seedcoats appear grey against a green chlorenchyma background and tan against a yellow chlorenchyma background.
from Loy, J.B. 1990. Hull-less seeded pumpkins: a new edible snackseed crop. p. 403-407. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.
