1918] Yocum: The Neuromotor Apparatus of Euplotes Patella 383 



the commissure between the blepharoplasts and in the anterior ehiasma, 

 two organisms are thus integrated into one individual. 



The above series of five examples gives an idea of the progressive 

 development of the neuromotor apparatus from the simple Naegleria 

 type to the more complex coordinating type of Giardia. In all, the 

 common characters are flagella, blepharoplast, and nucleus. Such a 

 structural relationship shows that the nucleus is the kinetic center of 

 all activity. As was shown by Kofoid and McCulloch (1916) and 

 Swezy (1916), the parabasal body is not a kinetonucleus but rather 

 it is a kinetic reservoir, the volume of which fluctuates according to 

 the physiological condition of the animal. 



Homology op Neuromotor Apparatus in Ciliates and Flageli,ates 



We shall now return to a consideration of how far we can homolo- 

 gize the neuromotor apparatus of ciliates with that found in flagellates. 

 An homology is rather difficult to establish, but there are at least two 

 facts which seem to indicate that the structures are similar to a 

 certain extent. 



The first is the homology of the blepharoplast with the motorium, 

 based upon the relation of these structures to the motor organs of 

 their respective organisms. As we have seen in the brief review of 

 the neuromotor apparatus of flagellates, the blepharoplast is the central 

 structure with which the flagellar apparatus is connected. All motor 

 organs, both intra-cellular and extra-cellular center upon this one 

 body. Such a condition is not only true for the uninucleated forms 

 but is equally true for the multinucleate forms such as StepJian- 

 onympha and Calonympha as described by Janicki (1915). In these 

 forms there are many blepharoplasts, each connected with certain 

 flagella and intra-cytoplasmic fibers, comparable to rudimentary axo- 

 styles. In all these the blepharoplasts are each connected with a 

 nucleus. 



In ciliates we have a system of structures which at first sight 

 appear to be quite unlike any structures found in flagellates, but 

 between which, upon careful analysis, there is a probable similarity. 

 This similarity exists between the blepharoplast of the flagellate and 

 the motorium as described for Diplodinium ecaudatum and Euplotes 

 patella. As brought out above, the blepharoplast is the center around 

 which the motor structures are built and as such may be taken as the 

 coordinating organ serving to regulate the anterior and posterior 



