. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FEEDING REACTIONS IN DILEPTUS GIGAS. 117 tures are capable of enormous expansion at the time of feeding. Normally, however, they are closed except for a pit-like cavity which is always present. A cytopyge is sometimes discernible near. FIG. i. Diagrammatic sketches of Dileptus gigas: A. side view; B, oral view ; v, contractile vacuoles : p, proboscis ; m, mouth ; c. cross section of pro- boscis ; r, bands of large cilia. the posterior end, at which place faecal material often collects in a large vacuole from which it is spor
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FEEDING REACTIONS IN DILEPTUS GIGAS. 117 tures are capable of enormous expansion at the time of feeding. Normally, however, they are closed except for a pit-like cavity which is always present. A cytopyge is sometimes discernible near. FIG. i. Diagrammatic sketches of Dileptus gigas: A. side view; B, oral view ; v, contractile vacuoles : p, proboscis ; m, mouth ; c. cross section of pro- boscis ; r, bands of large cilia. the posterior end, at which place faecal material often collects in a large vacuole from which it is sporadically discharged. There are numerous contractile vacuoles of which the larger ones are ar- ranged in a series near the aboral surface. Thin contractile fibrillae extend around the body in the form of a flat spiral, effect- ing about one complete turn for the entire length of the body. The entire body is covered with short cilia which run in rows parallel to the fibrillce. On the ventral surface of the proboscis, which is somewhat flattened, the cilia are considerably thicker and longer than elsewhere, especially along the edges, where they are in the form of two bands. These extend backward in such a way as to meet and form an arch just behind the mouth opening. Since all these cilia beat backward under normal conditions, a decided current is produced in the groove between these two bands of large cilia. This current starts at the tip of the proboscis and runs back to the mouth, where it ends in a sort of vortex, due to the action of the band of cilia which partially surrounds this pit- like orifice as above described. Structures which have been quite generally described as trichocysts are found in the oral surface of the proboscis. They can be seen only indistinctly in living mate-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly re
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
