62 



PROTOZOOLOGY 



which have connections with the fiagella as seen in certain Hyper- 

 mastigina such as Lophomonas. 



In trichomonad flagellates there is often present along the line of 

 attachment of the undulating membrane, a rod-like structure which 

 has been known as costa (Kunstler) and which, according to Kirby's 

 extensive study, appears to be most highly developed in Pseudo- 

 trypanosoma and Trichomonas. The staining reaction indicates that 

 its chemical composition is different from that of fiagella, blepharo- 

 plast, parabasal body, or chromatin. 



Fig. 21. a, trichites in Spathidium spathula, X300 (Woodruff and 

 Spencer); b, trichites in Pseudoprorodon fardus, X400 (Roux). 



In the gymnostomatous ciliates, the cytopharynx is often sur- 

 rounded by rod-like bodies, and the entire apparatus is often called 

 oral or pharyngeal basket, which is considered as supportive in 

 function. The rod-like bodies appear in most cases to be trichites 

 which may have been derived from the trichocysts, but which do not 

 explode as do the latter. For example, in Chilodonella cucuUulus the 

 oral basket is composed of 12 trichites which are so completely 

 fused in part that the lower portion appears as a smooth tube and 

 in Pseudoprorodon farctus (Fig. 21, h) much longer trichites form the 

 basket, with reserve structures scattered throughout the cytoplasm 

 (Engelmann). In Spathidium spathida (Fig. 21, a), trichites are 

 imbedded like a paling in the thickened rim of the anterior end. They 

 are also distributed throughout the endoplasm and, according to 

 Woodruff and Spencer, ''some of these are apparently newly formed 

 and being transported to the oral region, while others may well be 



