This is very basic Mendilian Theory
Mutation: Group II Yellow
This was first shown on the Clivia Forum
(http://www.cliviaforum.co.za/forum/index.php?topic=1602.0)

Here is a quick How to...on Group 2 Yellow Group 2 Yellow crossed to Group 2 Yellow, results in 100% Group 2 Yellow Wildtype Orange crossed with Group 2 Yellow results in 100% Orange split Group 2 Yellow Orange split G2 Yellow crossed to G2 Yellow, results in 50% Orange split G2 Yellow and 50% G2 Yellow Orange split G2 Yellow crossed to Orange split G2 Yellow, results in 50% Orange/G2 Yellow, 25% G2 Yellows and 25% Orange

Gardens... should be like lovely, well-shaped girls:  all curves, secret corners, unexpected deviations, seductive surprises and then still more curves.  
~H.E. Bates, A Love of Flowers

Clivia, Clivia Forum, gardenii, nobilis, caulescens, mirabillis, miniata, Clivia Base, robusta, Chinese Clivia, Clivia Seeds, seed, seed list, palm seed, cycad seed, white clivia, near white clivia, clivia sales, seed sales, ferns, clivia seedlings.