The Early Development of the Rostellum of Cysticercus fasciolaris Rud., and the Chemical Nature of Its Hooks

Abstract

This study is based on stained sections of numerous bladderworms of C. fasciolaris obtained from 393 naturally infected rats (Rattus r. kandianus) from Colombo, Ceylon. Detailed descriptions are given of the origin and development of the scolex-anlage, the early development of the rostellum and the rostellar rearrangements, the structure and development of cuticle, cuticular "hairs," hooklets and definitive hooks. These results are discussed in the light of earlier work on C. pisiformis, Echinococcus and C. longicollis. By an application of Campbell''s modified van Wisselingh-Brunswik tests for chitin, the hook-substance of C. fascinlaris is shown to be not of the nature of chitin. From the positive Biuret, Xanthoproteic, Millon''s, Saka-guchi''s and sodium plumbite reactions obtained, it is concluded that the hook-substance closely resembles a sclero-protein of the keratin type.