Title: American journal of physiology Identifier: americanjourna03ameruoft Year: 1898 (1890s) Authors: American Physiological Society (1887- ); American Physiological Society (1887- ). Abstracts of papers presented at the fall meeting; American Physiological Society (1887- ). Proceedings Subjects: Physiology; Physiology Publisher: [Bethesda, Md. , etc. ] American Physiological Society [etc. ] Contributing Library: Gerstein - University of Toronto Digitizing Sponsor: University of Toronto

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Text Appearing Before Image: 244 H. S. yami Jigs. ah o. { b) Localized chemical stimuli. — If a crystal of XaCl or a capillary glass rod coated with methyl green is held in front of a resting Dilep- tus, there is for a moment no response. Then as the diffusing chem- ical reaches the animal, it darts backward, thus escaping from the advancing flood without injury. If the chemical is placed some distance behind the Dileptus, as the diffusing chemical reaches it the animal darts backward, as before, thus approaching and entering the dense solution, where it ma)- be killed. If the chemical solution comes from one side, the same reaction is given, — the direction of motion being then neither toward nor away from that from which the solution is coming. If the animals are dropped directly into a weak chemical solution, the reaction is likewise the same. There is thus no sign in the reaction to a chemical of any relation to the localization of the stimulus. It seems probable that no reaction occurs until the diffusing chemical has reached the sensitive anterior end of the animal; then the typical reflex is given without relation to the direction from which the chemical came. Loxodes rostrum O. F. M. — Description.— Loxodes rostrum (Fig. 10) is a very large infusorian, of a flattened elongated form, the anterior end pointed and curved toward the oral side; the posterior end likewise O. F. M., after Biitschli. pointed or sometimes blunt. One of the a, anterior end; /.posterior sides js convex, the other deeplv furrowed. end; o, oral side; a b, ab- „, . .. , ,., ,x oralside The mouth lies on one edge (the oral), not far from the anterior end. Owing to its large size and the slowness of its motion, Loxodes is an espe- cially favorable form for observing the effects of localized stimuli. Movements. — Loxodes moves very slowly, at times creeping along the substratum on one side, at times swimming freely through the water. In the former case the path is nearly or quite straight; in the latter case the animal revolves and the path is a spiral, the aboral edge lying to the outside of the spiral.

Text Appearing After Image: Figure io. Loxodes rostrum

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