Direct contact method of autoradiography was utilized in studying the distribution of exogenous C(14)-proline in Clonorchis sinensis, Eurytrema pancreaticum, Hymenolepis diminuta and Dipylidium caninum. The most distinct autoradiogram were obtained after 60 min of incubation, corresponding to the maximal absorption of C(14)-proline in these parasite. The radioactivitity of this labeled amino acid was chiefly concentrated in reproductive organs, especially egg-containing uterine tubules.
