Abstract
The fibrillar system of ciliate protozoöns was described by Sharp for Diplodinium, by Yocom for Euplotes. An integrated fibrillar system in the flagellate Giardia was described by Kofoid and Christiansen and for Trichonympha and Trichomitus by Kofoid and Swezy. The designation neuromotor apparatus has been given to this integrated organ system of the Protozoa, on the basis of morphological considerations and anatomical relations. Experimental proof of the conductile function of certain elements in this system has been accomplished in Euplotes by microdissection with the Barber apparatus. With this instrument actuating quartz microscalpels it has been possible to cut selected fibrils and determine the effects of the cutting and subsequent regeneration upon the previously analyzed stereotyped behavior of this organism.
Euplotes patella is a hypotrichous ciliate protozoon about 100-150 microns in length. Its neuromotor system consists of a small bilobed central mass, the motorium, at the corner of the cytostome. From this a fiber runs anteriorly and to the left at the base of the membranelles the full length of the adoral zone connecting with the bases of these motor organs. An extensive fibrillar lattice-work in the anteriorly projecting oral lip appears to be connected with this fiber. Running posteriorly from the motorium five distinct fibers diverge posteriorly, one each to the five posteriorly located anal cirri. No such fibers pass to the other thirteen cirri, but radiating fibrils from the base of each disappear in the adjacent cytoplasm. There is thus an integrated fibrillar system connecting the presumably sensory anterior lip, the powerful motor oral membranelles and the five major cirri of the ventral surface most active in the walking and swimming movements of the animal.
Structural relations do not indicate a supporting or skeletal function for these fibers.
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