Certain of the cysts have been found in a ruptured condition, whereby the spores have been liberated into the surrounding tissue. It is almost certain that the spores serve for the auto-infection of the host, for though the tumours of Rhinosporidium seemed to have been removed entirely, it has been found that they recur, some minute fragment of the parasite having probably been left behind. The method whereby the parasite reaches new hosts has not yet been determined, and it would be of interest if its life-history could be more fully investigated.
[Illustration: FIG. 112.--_Rhinosporidium kinealyi._ Portion of ripe cyst containing pansporoblasts of various ages. × 480. (After Minchin and Fantham.)]
The Asiatic specimens of _R. kinealyi_ were first described in detail by Minchin and Fantham (1905) from material briefly reported to the Laryngological Society of London in 1903, by O’Kinealy. Material obtained by Dr. Nair, of Madras, was described by Beattie[241] in 1906. This material came from Cochin. Castellani and Chalmers have found similar polypi in Ceylon.
[241] _Journ. Pathol. and Bacteriol._, xi, p. 270; and _Brit. Med. Journ._, Nov. 16, 1907, p. 1402.
Wright[242] has described the parasite from Memphis, Tennessee. Seeber[243] in 1896 described nasal polypi in Buenos Ayres, and in 1900 Wernicke named the parasite therein _Coccidium seeberi_. Seeber’s parasite is a Rhinosporidium, _R. seeberi_, and may ultimately be found to be the same as _R. kinealyi_. Ingram[244] reports Rhinosporidium cysts, with pores in the cyst walls, in conjunctival polypus and in papilloma of the penis in India. Zschokke has reported the presence of _Rhinosporidium_ in horses in South Africa.
[242] _New York Med. Journ._, December 21, 1907, p. 1149.
[243] _La Ciencia Medica_ (Buenos Ayres), 1912.
[244] _Lancet_, September 3, 1910, p. 726.
Class IV. *INFUSORIA*, Ledermüller, 1763.
The Infusoria (or Heterokaryota, Hickson, or Ciliophora, Doflein) include the Ciliata and the Suctoria. A few authorities, including Braun, raise the Suctoria (or Acinetaria) to separate rank as a class, but this is not widely followed.
The body of the Ciliata usually is bilaterally symmetrical and is enveloped in a cuticle which has numerous openings for the protrusion of the cilia. Most kinds have a fixed shape, whilst changes in the form of others are brought about by the contractions of the body substance. The latter exhibits hyaline ectoplasm, in which myonemes, and occasionally also trichocysts (minute spindle-shaped bodies) appear, and granular endoplasm which may contain numerous vacuoles. The cilia, on whose various arrangements the classification is based, are always processes of the ectoplasm. Their form varies; they may be hair-like, or more rarely thorn-like, spur-like, or hook-shaped; undulatory membranes also may occur, which are probably composed of fused cilia.