. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 36 ACTINIARIA 4 wliite spot and often another one at the base of the tentacles. Oral disc yellowy-white, with brown streaks nrnmifl the mouth. Dimensions in very extended state to about 6 cm. long, commonly shorter, breadth — cm. Occurrence. Sweden. Bohuslan, Vaderoarne 8—10 fms., sand (Carlgren, Oestergren) together with E. longicornis, but less frequent than tliis species. — 60 fms. (Gunhild-Exp. 1878). Exterior aspect. The physa is well-developed. The scapus is provided with a thin, sUghtly adherent periderm, common
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 36 ACTINIARIA 4 wliite spot and often another one at the base of the tentacles. Oral disc yellowy-white, with brown streaks nrnmifl the mouth. Dimensions in very extended state to about 6 cm. long, commonly shorter, breadth — cm. Occurrence. Sweden. Bohuslan, Vaderoarne 8—10 fms., sand (Carlgren, Oestergren) together with E. longicornis, but less frequent than tliis species. — 60 fms. (Gunhild-Exp. 1878). Exterior aspect. The physa is well-developed. The scapus is provided with a thin, sUghtly adherent periderm, commonly of a dirty-grey colour. The in- sertions of the mesenteries are conspicuous, apparently neither the scapus nor the capitulum are polygonal, at least not in extended state. The nemathybomes are not visible to the naked eye, wherefore the scapus seems to be devoid of them. They do, however, ap- pear in great numbers and are mostly irregularly packed together in groups (textfigs. i6b, 25, 26, com- pare the anatomical description). The tentacles are 16 in number, now very short, cylindrical, not pointed, now conical and longer. The arrangement of the tentacles in two cycles is not as distinct here as in other Edwardsia-s^eciQS, at any rate not when the tentacles are short. The oral disc and the actino- pharynx are of usual appearance, the latter provided with 8 longitudinal furrows of which the ventral one is the broader and forms a weak siphonoglyphe. Anatomical nemathybomes. Fig. 27. Textfigs. 25—27. Transverse sections of the scapus between two mesenteries of Edivardsia pallida (figs. 25, 26) and Edward- sia danica (fig. 27). ne: nemathybomes. Fig. 25 is drawn from an expanded specimen, fig. 26 from a contracted, fig. 27 from a ^f |-]jg gcapus are comparatively Small and usually col- rather much contracted specimen. lected in irregular groups; here and there a single nemathybome appears. In the aggregates the nemathybomes are \'ery closely packed, sepa
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectscienti, bookyear1921
