. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 20 ZOANTHARIA that in the furrows of the capitular region it is only separated from the ectoderm by a very small part of the mesogloea, which in this region is generally higher than in the other parts of the body and contains some nematocysts. The tentacles have the usual structure. Besides the very numerous spirocysts the ectoderm contains numerous, thick-walled capsules (length 14—17 /y>) and a few capsules of the same appearance as in the body-wall (length 24—26 /i, breadth 10 ft). The ectoderm of the oral disc is very
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 20 ZOANTHARIA that in the furrows of the capitular region it is only separated from the ectoderm by a very small part of the mesogloea, which in this region is generally higher than in the other parts of the body and contains some nematocysts. The tentacles have the usual structure. Besides the very numerous spirocysts the ectoderm contains numerous, thick-walled capsules (length 14—17 /y>) and a few capsules of the same appearance as in the body-wall (length 24—26 /i, breadth 10 ft). The ectoderm of the oral disc is very broad near the tentacles and contains numerous, closely packed spirocysts, near the mouth it is thinner and contains some nematocysts. The ectodermal longitudinal muscle layer is fairly strong in the outer part of the oral disc, weaker in the inner part. A layer of fibrillae and ganglion cells is distinctly visible in the oral disc. The ectoderm of the oesophagus is high and arranged in longitudinal folds supported by mesoglceal ridges, which emerge between the furrows. The nematocysts are scarce and thick-walled (length about 20 u). Large-grained gland-cells are found especially in the inner parts of the ectoderm. Ectodermal longitudinal musculature is absent in this species. At the base of the ectoderm of the oral rim there seem to be numerous cells and a thread-like layer. As far as I can see — the material was not so well preserved as could be desired — it consisted of a well-developed layer of ganglion-cells and nerve-fibrillae. The mesogloea is fairly thick; its upper part is provided with numerous cells which are scarce in the aboral part. The ectoderm of the siphono- glyphe is of the usual structure and lower than in the other part of the oesophagus. The mesogloea is broad and much thicker than in the oesophagus. The hyposulcus has the same structure as the siphonoglyphe but the entodermal muscles here run in longitudinal direction and form some folds in the ou
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectscienti, bookyear1913
