Proteins and Lipoproteins in Yolk from Eggs of the Estuarine Crocodile (crocodylus Porosus); a Comparison with Egg Yolk of The

1. The livetin patterns of the two species Crocodylus porosus and Gallus domesticus were very different and it was difficult to find a correspondence. 2. In C. porosus the granules were a larger proportion of the total yolk but they contained very little lowdensity lipoprotein when compared with granules from hens' eggs. 3. The low-density lipoprotein was a lower proportion of the yolk of C. porosus: 30% of the dry weight compared with 60% for the hen. Furthermore, the former apparently contained an unstable fraction consisting of large particles. 4. The apoprotein patterns of the low-density lipoprotein of C. porosus eggs had a higher proportion of high-molecular weight constituents than that of the hen. 5. A glycoprotein with M, approximately 2 x 10 has been isolated that does not correspond to a known avian protein. 6. The characteristic protein of avian egg yolk, apovitellenin I, if present, was a minor constituent.