. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. ACTINIARIA 179 ing cells (PI. 4 fig. 9), here and there a granulous gland cell was observed; on the other hand, there were no nematocysts, excepting in the rim of the spots, where tliey are, however, ver>' rare. In the other part of the columnar ectoderm, the nematocysts, as well as the gland cells, were numerous. Of the gland cells some, the fewer, were more homogeneous, the , the more numerous, contained a multitude of small brownish granulae. Whether the latter, which often re
. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. ACTINIARIA 179 ing cells (PI. 4 fig. 9), here and there a granulous gland cell was observed; on the other hand, there were no nematocysts, excepting in the rim of the spots, where tliey are, however, ver>' rare. In the other part of the columnar ectoderm, the nematocysts, as well as the gland cells, were numerous. Of the gland cells some, the fewer, were more homogeneous, the , the more numerous, contained a multitude of small brownish granulae. Whether the latter, which often reach a considerable size, are gland-cells of the same kind as the former, but in a differ- ent state of secretion, I cannot with certainty decide. Possibly the circumstance that I have not obser\'ed any such in the unpigmented specimens, speaks in favour of tliis suggestion, though I hardly believe tliis to be the case. In the unpigmented specimens the homogeneous gland-cells were, however, numerous, but the ectoderm of these specimens was not as well preserved as in the specimens with spots. As above mentioned, there were in some specimens frag- ments of a cuticle which is evidently easily deciduous. The cuticle seems to be very thick but incompact and cracked, and not of typical appearance. The nie- sogloea of the column is thick and contains rather sparse protoplasma-poor cells. The endodermal circular muscles are very well developed and form high, deUcate, ramificated folds; in the region of the sphincter the muscle layer is weaker. The sphincter is strong and of a somewhat variable type. In a specimen it was on transverse sections round and distinctly palmate without a main lamella, and with a tendency (on some sections) to form meshes, in two other specimens it was compressed and of variable structure in different sections of the same spec- imen, now there was no distinct main lamella but rather several longitudinal la- mellae in the middle of the sphincter, now these latt
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Keywords: ., bookcentury1800, bookdecade1890, booksu, booksubjectarcticregions
