. Text-fig. 31. Caenagnesia bocki Arnback (St. 42): A, specimen with test removed; B, dorsal tubercle. Internal structure. The 'Discovery' specimens show remarkable agreement with Arnback's detailed account. The numerous oral tentacles are arranged in five distinct circles. The rectum appears to be a little shorter than that shown in Arnback's fig. 20. Remarks. This species has been recorded only twice before; off Graham Land (Arnback, 1938), and off Enderby Land (Kott, 1954) if we accept Agnesia complicata Kott as a synonym of C. bocki. Kott's description of the specimens which she examined f
. Text-fig. 31. Caenagnesia bocki Arnback (St. 42): A, specimen with test removed; B, dorsal tubercle. Internal structure. The 'Discovery' specimens show remarkable agreement with Arnback's detailed account. The numerous oral tentacles are arranged in five distinct circles. The rectum appears to be a little shorter than that shown in Arnback's fig. 20. Remarks. This species has been recorded only twice before; off Graham Land (Arnback, 1938), and off Enderby Land (Kott, 1954) if we accept Agnesia complicata Kott as a synonym of C. bocki. Kott's description of the specimens which she examined from near Enderby Land agrees very closely with Arnback's description of the type specimens, except in having a better developed branchial sac. In A. complicata there were twenty-four transverse rows of infundibula each with seventeen infundi- bula, as compared with twelve rows each with thirteen or fourteen infundibula in C. bocki. This difference can be accounted for by the larger size of the specimens from Enderby Land. Kott mentioned ' bifid languets' alternating with each transverse row of infundibula and not with each two rows (cf. A. septentrionalis Huntsman, A. glaciata Michaelsen, van Name, 1945, p. 201). These ' bifid languets' are in fact the bifid papillae which are present on the transverse vessels. True languets, to which Huntsman referred in A. septentrionalis, are present only along the roof of the branchial sac. Caenagnesia, having a continuous dorsal lamina, has no languets. Distribution. Antarctic (Graham Land, South Georgia, Enderby Land).
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