The terrestrial snail, Eobania vermiculata (Müller) was exposed to different concentrations (10-300 I.S/snail) of the snail parasitic nematode, Rhabditis sp. under laboratory conditions (26 ± 2 ^oC and 70 ± 5 R. H %). Period needed for snail death decreased from 5.75+ 0.64. to 1.7+0.14  days by increasing concentration from 10 IS/snail to 300IS/snail . Period from death to recovering nematodes became shortest 3.1+0.21 days at the concentration 200 I. S/snail  and longest 5.77+0.55 days at 20 I. S. Period needed for relaesing  nematodes was irregular and showed insignificant differences. Numbers of recovered nematodes were also irregular and not related to the nematode concentrations but showing very highly significant differences. Three groups of laboratory bred albino rats, Rattus norvegicus (five individuals/each) were also exposed to infection with the same nematode (5000 I. S/rat) by three methods ,oral, injection under skin and intrapretoneal injection. No mortality was found for these treatments and no individuals of all the treated rats showed any symptoms of abnormality.