Studies on the Balantidium from the guinea‐pig

Abstract

THREE mxrr FIGURES AND SIX PLATES .4UTHOR'S ABSTRACTObservations indicate that this Balantidium from thc guinea-pig is Balantidium coli, the form found in the pig and man. The lengths and breadths of this Balantidium and the ratios of length to breadth are very close to the measurements and ratios given by NcDonald for B. coli. When plotted, the body lengths of the guinea-pig parasites appear in two groups, the smaller individuals being the exconjugants. Many of these exconjugants resemble Neiva's B. caviae. The structure of the Balantidium from the guinea-pig is essentially identical with that of B. coli as given by McDonald.Fission and conjugation of this ciliate follow the general course found in a number of other ciliates. During fission the micronucleus divides and the daughter micronuclei migrate to each end of the macronucleus before the latter divides. I n conjugation there are two divisions of the micronucleus, one of these nuclei dividing to form the pronuclei. Pronuclear exchange and fusion are followed by a heteropolar division of the synkaryon, resulting in the formation of the new macronuclear and micronuclear anlagen.

Ciliates From Bermuda Sea Urchins* I. Metopus

“…In general, the macronucleus is uniformly granular ; it stains so intensely that its details are obscured. However, there are frequently observed in it globular condensations resembling those noted by the author in the macronucleus of Balantidium (Scott, 1927). The macronucleus is positive in its thymonucleic acid reaction to the Feulgen test.…”

Light and scanning electron microscopic study of Balantidium ctenopharyngodoni Chen, 1955 (Class: Litostomatea) from China

“…It is presumed that B. ctenopharyngodoni can go through the oral or anal opening of grass carp to complete the transmission because the trophozoites and cysts were only found in the gut, especially the hindgut. The former strategy resembles that of B. coli (Scott 1927). After ingestion by a fish host, the cyst can probably pass through the digestive system because the thick cyst wall protects it from degradation.…”

“…The genus Balantidium was established by Claparède and Lachmann in 1858 when they separated Bursaria entozoon, originally described by Ehrenberg in 1838, from the genus Bursaria and renamed it Balantidium entozoon under this new generic name (Scott 1927). Thereafter, many new species of Balantidium have been found from both vertebrate and invertebrate animals.…”

First report of two Balantidium species from the Chinese giant salamander, Andrias davidianus: Balantidium sinensis Nie 1935 and Balantidium andianusis n. sp.

“…The remaining (Scott 1927). b B. hyalinum was considered as a synonym for B. duodeni by Bhatia and Gulati (1927).…”