I assume your question is referring to CHO cells? If so they are generally an immortalised epithelial cell line, but there are various varieties of the cells available. So it would be beneficial for you to determine which you have.
I am not completely sure that there was one specific bit of the ovary he (T. Puck) used when generating the cell line (1957). But they are epithelial. You could try researching his articles to see if he explains it in there. Otherwise i would assume he dissociated whole ovary and CHO cells are what grew.