Abstract
By the cultivation method by filtration paper, the same as applied for rearing of larvae of hookworms, Strongyloides could be reared and detected easily from the feces in which few larval Strongyloides and many eggs of Ancylostma duodenale existed together. It was shown that the short period of cultivation, 3 days at 28°C, was enough for detecing Strongyloides, because after the 4th day the larvae of hookworms apoeared in a great number. Adult worms could be obtained from the paper, when it was put in a Petri dish, in which warm water 40°C. had been poured. After 30 minutes many males and females appeared in clear water.
In order to observe the time occurrences in culture media and morphological charactristics of each stage of Strongyloides, larvae was cultivated in feces which was emulsified in water, strained through a fine screen to exclude the gredients and centrifuged. In this culture medium at 20°C, rhabditoid larvae grew up to filariform larvae or males after 2 days, and to females after 3 days. However males appeared in few number during only 2 days.
The morphological charactristics of all free-living stages were illustrated in Figs.1 and 2. For the fine descriptions of them and the further studies on comparisons of them with rela' ed genuses and species, the position of main structures of worms were presented by two formulas, the distances from the head to each organ and the percentage of them by the body length as in Table 3, 4, 5.
