The number of cysts used for each replicate in a dilution hatching trial may be reduced to 10. Log. total hatch is used, instead of total hatch itself, and the mean for each dilution determined from the log. values; the logs, of these means, plotted against dilution in the usual way, gives a straight line as in the original Fenwick technique. Reduction of the number of cysts permits the use of commercially available utensils to form an easily handled set-up.