. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 32 MEDUSJE. I. funnel-shaped, with a wide opening into the corners of the stomach; the distal one-third of the radial canal is a narrow tube, communicating with the narrow circular vessel. The umbrellular part of the funnel-shaped canal is narrow, and from this part issue a large number of lateral folds or branches, perpendicular to the main canal. The umbrellular walls of these lateral folds are attached to the sub- umbrella, whence the folds hang as perpendicular lamellse, the \entral edges being free. Below the narrow, la
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 32 MEDUSJE. I. funnel-shaped, with a wide opening into the corners of the stomach; the distal one-third of the radial canal is a narrow tube, communicating with the narrow circular vessel. The umbrellular part of the funnel-shaped canal is narrow, and from this part issue a large number of lateral folds or branches, perpendicular to the main canal. The umbrellular walls of these lateral folds are attached to the sub- umbrella, whence the folds hang as perpendicular lamellse, the \entral edges being free. Below the narrow, lamelliferous part of the radial canal is the wide, funnel-shaped part, mentioned above, reaching out- wards nearly to the outermost (distal) lateral folds, gradually narrowing outwards and terminating in a point. The narrow dorsal part is separated from the wide ventral part by a longitudinal fold on each side (Plate III, figs. 2 and 3). These two folds continue in a centri- petal direction in the dorsal wall of the stomach nearly to the centre along both sides of each of the ciliated grooves (Plate III, fig. i). Towards the distal end of the funnel-shaped part the folds are gradually tapering; in the distal part of the folding system there is, accordingly, no complete separation between the ventral and the dorsal part of the canal. Thus a differentiation of the gastro-vascular system, similar to that in Laodicea undulata^ is established in this species. Probably the food is received and dissolved in the wider, ventral part (I have found half-digested copepods therein); the dorsal part only communicates with the ventral part for a short distance near the distal end of the funnel-shaped part. Proximally the dorsal part opens into the dorsal wall of the stomach through a narrow opening, distally it passes into the narrow, tube-shaped part of the radial canal, free of gonads, through which the dissolved nutritive substances, which have been carried from the funnel-shaped part into
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectscienti, bookyear1919
