Methods for obtaining plasma from anurans are unsatisfactory in that they are inadequately described, are difficult to perform, or are lethal to the subject. A lymph extraction technique involving temporary ligation is described that enables sufficient fluid to be obtained for analysis from frogs greater than 20 g. Lymph was more easily obtained from Bufo marinus than from the austral-hylids Litoria caerulea and Cyclorana australis. Lymph accumulation was faster in hydrated frogs or those with full bladders, whereas it was relatively slow in animals that had been dormant or that were dehydrated. Differences between the osmolality of lymph and blood-plasma were variable but slight; presumably the relatively high endothelial permeability of amphibians facilitates significant fluid exchange.