(full paper is archived in the Miller Library)
Title: Phototaxis and Photkinesis in Littorina planaxis
Student Author(s): Eckert, Dieter
Location: Final Papers Biology 175H
Date: June 1964
Abstract: Littorina planxis crawling on glass plates in the sunlight orient themselves primarily along the sun's rays. A response to the plane of polarization of the sunlight is the probably mechanism involved. L. planaxis behaves phokinetically, increasing both its rate of turning and tis rate of forward crawling at higher light intensities. The littorine eye, as tested by the tentacle jerk response, is sensitive on the light in the middle of the visible spectrum. Snails found on dry rocks were always photonegative. In either case, the response is strengthened by 24 hours of constant light or darkness.