484 OSCAR RIDDLE 
probably due to the fact that these spherules contain much fat, 
and the lipochrome pigment is soluble in fat and fat solvents only. 
17. The origin of the yolk of the fowl’s egg from the nucleus 
of this cell, or from the nuclei of the follicular cells, is shown to 
be impossible. It is not probable that the essential features of 
yolk synthesis in any egg resides in either of these alleged sources. 
18. An attempt is made to outline the processes involved in 
yolk formation. 
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