. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 2IO FOOTE AND STROBELL. on single worms, was to dump daily several pots, each contain- ing one hundred worms and carefully to examine the clitellum of each worm. The presence of a slime-tube, with or without a cocoon, can be detected, by constrictions at each end of the cli- tellum. These constrictions are very marked when the worm is contracted and difficult to see when the worm stretches out. When the worm succeeds in partially escaping from the slime- tube, one or both constrictions can be seen on, or near, the cli- tellu
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 2IO FOOTE AND STROBELL. on single worms, was to dump daily several pots, each contain- ing one hundred worms and carefully to examine the clitellum of each worm. The presence of a slime-tube, with or without a cocoon, can be detected, by constrictions at each end of the cli- tellum. These constrictions are very marked when the worm is contracted and difficult to see when the worm stretches out. When the worm succeeds in partially escaping from the slime- tube, one or both constrictions can be seen on, or near, the cli- tellum. These constrictions are produced by the slime-tube and. FIG. 3. A freshly deposited cocoon. Wnen on the worm the shorter end of the slime-tube is posterior to the clitellum and the impress of 5 segments on the tube shows that, in this case, the posterior end of the slime-tube extented to the 39th seg- ment of the worm. This figure was reduced one fourth from Fig. 3 of an earlier paper. The original figure was magnified seven diameters. not by the cocoon, for we have found worms showing marked constrictions, when careful examination of the slime-tube after removal, failed to show any trace of a cocoon. This indicates that the formation of the slime-tube is the first step in the process of forming a cocoon. Having established the fact that cocoons are formed by these worms, during copulation or separately, the opposing opinions on this point are harmonized. The question now remains, which method predominates ? We find eggs in the cocoon while it still encircles the cli- tellum, proving that they must be conveyed through the slime- tube, from the oviducts on the I4th segment, to the cocoon ; and that they are not deposited in the cocoon when it finally passes over these segments, as suggested by several investigators. We have found from one to twenty-eight eggs generally near the anterior end of the cocoon. In some cases these cocoons. Please note that these images are extracte
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
