Abstract
The scanning electron microscope was used to study the evolution of the infrastructure of cervical mucus in normal cyclic baboons and in castrated animals treated with ovarian hormones for establishing an artificial cycle. In both groups, the results make conspicuous the progressive enlargement of the filamentous woof, which attains a maximum at midcycle and then decreases by degrees in the second part of the cycle. It was shown that the evolution of the framework is very similar during normal and artificial cycle, with only variations of slight amplitude. Moreover, the variations in the baboon mucus infrastructure closely resemble those described in the human. The results are briefly discussed in the light of known data.