Protists and disease : vegetable protists: algae and fungi, including Chytridiineae, various Plassomyxinae, the causes of molluscum contagiosum, smallpox, syphilis, cancer, and hydrophobia together with the Mycetozoa and allied groups / by J. Jackson Clarke.

  • Clarke, J. Jackson (James Jackson), 1860-1940.
Date:
1922
Catalogue details

Licence: In copyright

Credit: Protists and disease : vegetable protists: algae and fungi, including Chytridiineae, various Plassomyxinae, the causes of molluscum contagiosum, smallpox, syphilis, cancer, and hydrophobia together with the Mycetozoa and allied groups / by J. Jackson Clarke. Source: Wellcome Collection.

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    water and transfer to tap water. Sporangia appear in 24 hours (Chamberlain). The thallus is normally an undivided sac, simple in Saprolegnia, branched in Adilya. Septa are formed to shut off reproductive organs or to repair injury. In agamic reproduction the end of a filament swells as a long sporangium, a septum isolating its contents, which subdivide into many uninucleate segments. In Saprolegnia these escape directly as bi-flagellate zoospores, in Adilya in a mass held together by a jelly, Figs. 3 and 4. The large sporanges of Saprolegnia with their central vacuole, cylindrical or irregularly linear, according to the thickness of the protoplasm, lend themselves to the study of the mode of origin of zoospores ; this has been described by M. Hartog and others ; seeing that corresponding stages are seen in Pythium and Chytridiineae, the leading features may be enumerated, following E. J. Butler’s account: 1, Preliminary separation of spore-origins by concentration of protoplasm around each nucleus, linear vacuoles occupying the intervals ; 2, homogeneous stage caused by swelling of spore-origins and disappearance of the sporangial vacuoles ; this stage has been explained as being due to rupture of the skin-layer admitting water to the spore-origins ; 3, vacuo- lation ; in the origins are formed a number of vacuoles, which grow, fuse, and disappear; discharging water into the exterior where the escaped cell-sap attracts bacteria ; 4, final separation of zoospores by surface grooves meeting