The development of the thymus, epithelial bodies, and thyroid in the Marsupialia. Part 1. Trichosurus vulpecula. [Abstract] / by Elizabeth A. Fraser and J.P. Hill. The development of the thymus, epithelial bodies, and thyroid in the Marsupialia. Part 2. Phascolarctos, Phascolomys and Perameles. [Abstract] / by Elizabeth A. Fraser.