| Popis: |
A number of species of chitons (mollusks) have radulae (tongues), that are covered by ferro-magnetic denticles. The radulae and shells of two previously untested species were studied. The radulae of Acompapleura granulata (Gmenin) and Chiton Squamosis (Linne) were found to be ferro-magnetic but the shells were not. Live specimens of the chiton, Chaetopleura apiculata, that also have ferro-magnetic radulae, were observed in a weak magnetic field and the earth's field. Results from three indexes of movement under these two conditions show that animals rotate more and move farther in a weak than in the earth's magnetic field. These results together with others suggest that the chiton is responsive to magnetic fields and shows kinetic movements within them. |
