Rates of ingestion were measured for 9 groups of invertebrate cryptozoans, utilizing radioactive tracer turnover rate measurements. These groups were Diplopoda, Cryptostigmata, Pulmonata, Mesostigmata, Collembola, Orthoptera, Coleoptera, and 2 groups of Araneida. The radioisotopes134Cs and85Sr were considered as the metabolic analogs of potassium and calcium, respectively. Feeding rates were calculated as the ingestion necessary to maintain body pools of these elements. Values obtained were somewhat lower than results reported by others, possibly due to inflated estimates of assimilation for the radioisotopes.