. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 32 MEDUSA. 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 lamellae, the ventral edg
. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 32 MEDUSA. 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 lamellae, the ventral 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 tlT£ 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 iiiidiiltifa^ 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 onh- communicates with the \entral part for a short distance near the distal end of the funnel-shaped part. Proximally the 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 bee
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Keywords: ., bookcentury1800, bookdecade1890, booksu, booksubjectarcticregions
