378 University of California Publications in Zoology [Vol. 18 



DISCUSSION 



Fibrillar Systems in Other Ciliates 



The term, neuromotor apparatus, is of late origin, being first used 

 by Sharp (1913) to denote a new structure found in Diplodinium 

 ecaudatum. This structure, from its staining reaction and its anatom- 

 ical relationships, was interpreted as having a neuromotor function. 

 Few structures like this have been described for ciliates. Engelmann 

 (1880) was the first to call special attention to such distinct fibers. 

 These he described in Stylonychia, extending from the peripheral cirri 

 into the central part of the animal. These have been seen many times 

 by me on slides made for a study of Euplotes, for Stylonychia and 

 Euplotes are usually associated in the same cultures. To these fibers 

 Englemann (1880) assigned a nervous function, but later writers such 

 as Biitschli (1889), Schuberg (1891), and Maier (1903) discredited 

 such ideas and instead gave the fibers the functions either of support 

 or possible contraction. Maupas (1883) found fibers in Euplotes 

 similar to those described in this paper as previously noted. Prowazek 

 (1903) has described such fibers for E. harpa and Grilfin (1910) has 

 found them in E. worcesteri. In these two species of Euplotes the 

 function of contractility is ascribed to the fibers. Neresheimer (1903), 

 working on Stentor coeruleus, found certain fibers to which he ascribed 

 a nervous function. However, he found two sets of fibers in the 

 "zwischen streifen. " One of these he called the myophane, indicating 

 that it was contractile, the other he called the neurophane, indicating 

 that it was of a nervous character. There seem certain reasons why 

 such names are not appropriate : The first of these is that in staining 

 with Mallory's stain those structures which have an affinity for the 

 acid fuchsin are supposed to have a nervous function. In the work 

 of Neresheimer structures taking this stain are called myophanes. 

 Secondly and more significant, is the fact that the so-called myophanes 

 are indicated as being more closely related to the basal granules of 

 the cilia than are his neurophanes. In the later works, such as that 

 of Sharp (1913) on Diplodinium and this work on Euplotes, the cilia, 

 or at least the component cilia of the membranelles and cirri are shown 

 to be associated with fibers to which are ascribed a nervous function, 

 not to the absolute exclusion of the idea that they may possibly be 

 contractile in their function, but with the idea that they are more 

 nervous than muscular. 



