MORPHOLOGY 55 



pharynx and nucleus are also connected with these fibrils, ten 

 Kate suggested morphonemes for them, since he believed that the 

 majority were form-retaining fibrils. 



The well-coordinated movement of cilia in the ciliate has long 

 been recognized, but it was Sharp (1914) who definitely showed 

 that this ciliary coordination is made possible by a certain fibrillar 

 system which he discovered in Epidinium {Diplodiniutn) 

 ecaudatum (Fig. 16). Sharp recognized in this ciHate a complicated 

 fibrillar system, connecting all the motor organellae of the cyto- 

 stomal region, and thinking that it was "probably nervous in 

 function," as its size, arrangement and location did not suggest 

 supporting or contractile function, he gave the name neuromotor 

 apparatus to the whole system. This apparatus consists of a 

 central motor mass, the motorium (which is stained red with 

 Zenker fixation and modified Mallory's connective tissue stain- 

 ing), located very deeply in the ectoplasm just above the base of 

 the left skeletal area, from which definite strands radiate : namely, 

 one to the roots of the dorsal membranellae (a dorsal motor 

 strand); one to the roots of the adoral membranellae (a ventral 

 motor strand); one to the cytopharynx (a circum-oesophageal 

 ring and oesophageal fibers); and several strands into the ecto- 

 plasm of the operculum (opercular fibers). A similar apparatus 

 has since been observed in many other ciliates: Euplotes (Yocom; 

 Taylor), Balantidium (McDonald), Paramecium (Rees; Brown; 

 Lund), Tintinnopsis (Cambell), Boveria (Pickard), Dileptus 

 (Visscher), Chlamydodon (MacDougall), Entorhipidium and 

 Lechriopyla (Lynch), Eupoterion (MacLennan and Connell), 

 Metopus (Lucas), Troglodytella (Robertson), Oxytricha (Lund), 

 Ancistruma and Conchophthirus (Kidder), etc. 



Euplotes patella, a common free-living hypotrichous ciliate, 

 has been known for nearly 50 years to possess definite fibrils 

 connecting the anal cirri with the anterior part of the body. 

 Engelmann suggested that their function was somewhat nerve- 

 like, while others maintained that they were supporting or con- 

 tracting in function. Yocom (1918) traced the fibrils to the mo- 

 torium, a very small bilobed body (about S^t by 2yu) located close 

 to the right anterior corner of the triangular cytostome (Fig. 17). 

 Joining with its left end are five long fibers from the anal cirri 

 which converge and appear to unite with the motorium as a single 

 strand. From the right end of the motorium extends the mem- 



