Many attempts have been undertaken to make permanent preparations of helminth eggs. However, the resulting preparations either lacked durability or tended to deform thin-shelled eggs, such as those of the hookworm. To overcome these drawbacks, we have modified 2 aspects of the glycerin-jelly mounting procedure. First, we gradually changed the media in which the helminth eggs soaked, from 10% formalin via water to a 70% ethanol and 5% glycerin solution. It took 10 days, which is much longer than the time required for the processes previously reported. Second, we used a hole slide glass instead of a slide glass. Eggs of 11 species of helminths have been prepared with this procedure, and have kept their morphology without apparent change for more than 4 yr.