'Prothyalosomata' definitions:

Definition of 'Prothyalosomata'

From: GCIDE

Pro thyalosoma \Pro* thy`a*lo*so"ma\, n.; pl. Prothyalosomata. [NL., fr. Gr. prw^tos first + "y`alos glass + ?, ?, body.] (Biol.) The investing portion, or spherical envelope, surrounding the eccentric germinal spot of the germinal vesicle. [1913 Webster]