Here you see a section through a complete corpus luteum. The corpus luteum arises from the remnants of the follicle after ovulation.

You see a light part in the middle with connective tissue and outside that a convoluted reddish band (which consists of epithelial cells of the follicle, even if you cannot see cells with this magnification). You may notice that the reddish band consists of somewhat differently coloured areas – an outer thin, darker brim and a lighter inner main part. This represents the two kinds of endocrine cells in the corpus luteum (theca lutein cells and granulosa lutein cells, to be seen more clearly in the next photomicrographs). Ovarian tissue is seen down to the left and as a dark brim along ther lower edge of the corpus luteum.