. Bulletin of the British Museum (Natural History) Zoology. . Variations in shape of cothurnid loricas (following the terminology of Precht, 1935). Fig. 2 Normal lorica. Fig. 3 Normal aperture viewed from above. Fig. 4 Lorica with a curved neck. Fig. 5 Curved lorica. Fig. 6 Oblate lorica. Fig. 7 Prolate lorica. Figs 8-10 Dorso-ventrally compressed lorica, fig. 8 ventral view, fig. 9 lateral view, fig. 10 aperture viewed from above. aperture. Ideally several individuals should be measured and the range of variation given. Among other peritrichs it has been suggested that the ratio of length: wi
. Bulletin of the British Museum (Natural History) Zoology. . Variations in shape of cothurnid loricas (following the terminology of Precht, 1935). Fig. 2 Normal lorica. Fig. 3 Normal aperture viewed from above. Fig. 4 Lorica with a curved neck. Fig. 5 Curved lorica. Fig. 6 Oblate lorica. Fig. 7 Prolate lorica. Figs 8-10 Dorso-ventrally compressed lorica, fig. 8 ventral view, fig. 9 lateral view, fig. 10 aperture viewed from above. aperture. Ideally several individuals should be measured and the range of variation given. Among other peritrichs it has been suggested that the ratio of length: width is a more meaningful character than size alone (see Warren, 1987), and this may also prove to be the case for cothurnid loricas. descriptions of cothurnids and have long been recognised as useful characters for separating species. Jankowski (1985) suggested that the presence or absence of mesostyles and endostyles should be regarded as generic characters although acceptance of this decision must await further studies. Stalks All cothurnids possess a non-contractile external stalk attach- ing the lorica to the substratum. Some authors (Entz, 1884; Jankowski, 1985) have suggested that the size of the stalk and the presence of transverse folds on its surface are generic characters. In this revision stalk size and surface folding are not employed at the generic level although they are used for separating species. A few species appear to have a special tube at the posterior end of the lorica through which the external stalk penetrates the lorica wall (Banina and Polyakova, 1977). Mesostyles and endostyles are frequently included in Zooids The taxonomy of aloricate peritrichs is based largely on characters relating to the zooid (Foissner, 1981; Warren, 1987), frequently omitted from species descriptions of cothurnids. Descriptions available are often from studies made on fixed, contracted cells yielding information of limited value. The following zooid characters are useful; size
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