. A manual of zoology. 140 MANUAL OF ZOOLOGY many times, often hundreds of times, the greatest breadth, so that the animal assumes the form of a long, narrow ribbon or tape. This ribbon is not continuous, but is made up of a string of segments or proglottides. Towards one end the body becomes narrower, terminating in a rounded knob — the head or scolex. On the head (Fig. 75) is a circlet of hooks borne on a rounded prominence, the rostellum, which is capable of being protruded and retracted to a certain extent; at the sides are four suckers. By means of these hooks and suckers the head is atta
. A manual of zoology. 140 MANUAL OF ZOOLOGY many times, often hundreds of times, the greatest breadth, so that the animal assumes the form of a long, narrow ribbon or tape. This ribbon is not continuous, but is made up of a string of segments or proglottides. Towards one end the body becomes narrower, terminating in a rounded knob — the head or scolex. On the head (Fig. 75) is a circlet of hooks borne on a rounded prominence, the rostellum, which is capable of being protruded and retracted to a certain extent; at the sides are four suckers. By means of these hooks and suckers the head is attached to the wall of the intestine of the host, the elongated body lying free in its interior. The part of the body just behind the head {neck) is not divided into segments. The most anterior segments are much shorter than those further back, and not so distinctly separated off from one another. The surface is devoid of cilia, as in the Trematodes. A digestive cavity is, as already stated, absent; but there is a distinct nervous system, and a system Fig. 75.—Head of Taenia of water-vessels with flame-cells. In the solium, magnified. (After Leuckart.) posterior region of the body each pro- glottis (Fig. 76) is found to contain a complete set of hermaphrodite reproductive organs similar in general plan to those of the liver-fluke. The ova, when fertilised, are enclosed in a chitinoid shell, and received into a uterus. In the most posterior segments the uterus is a large branched tube distended with enormous quantities of these eggs, and the other parts of the reproductive appa- ratus have become absorbed. These " ripe " proglottides, as they are termed, drop off, one by one, from the pos-. 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 resemble the original Parker, T. Jeffery (Thomas Jeffery), 1850-1897; Haswell, Will
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