EN
Crowded infrapopulations of H. diminuta obtained from the WMS i11 inbred line resembled those of the potentially non-inbred WMS strain in not showing either the abrupt reductions in the numbers of worms or the destrobilation described by other autors. Denser populations of both types of tapeworm have a greather abundance of 4 - testis proglottids of the lp3a type (having 1 testis on the poral side and three on the aporal), and fewer of type 0p3a. Changes in the positioning of genital ducts and pores show a marked positive correlation with the abundance of type 2pla proglottids. Strobilae of H. diminuta WMS i11 contain a relatively greather number of type 0p3a proglottids and fewer of type 1p3a, than those of the WMS „strain"; something which is probably linked with the respective selection of the maternal Tapeworms.