Introduction

Mumford (1940) has suggested that many of the early studies in the Pacific give an erroneous picture of the protozoan fauna of the area, since many species have been recorded as new because of their occurrence in an isolated locality and in relation to inadequate descriptions of the species elsewhere. This seems to have page 2 been the case in this country, at least with ciliates, where Kirk (1885), Maskell (1886, 1887), and Schewiakoff (1892) recorded 91 species, of which nearly half were described as new. In the present studies, 32 species of ciliates have been observed, but only four are new, and none of the earlier described New Zealand species have been seen. The evidence now indicates that the free-living ciliate fauna of this country is largely cosmopolitan, but has some new species, possibly endemic, but probably cosmopolitan and awaiting discovery elsewhere.

Of the species in this account, one belongs to the genus Glaucoma, two to Stentor, and one to Uroleptus. Furgason (1940), in a detailed study of the Glaucoma-Colpidium group, gives a valuable revision of the systematics, and stresses the importance of the morphology of the ingestive apparatus and silver-line system in the group. The new species of Glaucoma has been established on details of the ingestive apparatus, nuclear complex, and other structures, which differ from the corresponding structures described in other species by Kahl (1926), Gelei (1936), and Furgason. A silverline study would have been undertaken had its importance been realized before cultures were discarded. The literature on Uroleptus and Stentor has not been reviewed in a manner comparable with that of Furgason for the Glaucoma-Colpidium group. Kent (1880–1882), Stokes (1888), Roux (1901), Sokoloff (1930), and to a lesser extent Maskell (1886, 1887) and Kudo (1946) all report or describe species of both genera. Kahl's re-description of Stentor igneus (1932) is not available, but Kudo reproduces his figure of this species and from this, and previous descriptions, it has been possible to indicate the distinctive nature of the present material. Uroleptus halseyi Calkins (Calkins, 1929) appears to be the latest description of a species of Uroleptus, but the present material shows characteristic differences from this and earlier described species.