TRICHOMONAD FLAGELLATES. 311 



forms. In moribund individuals tiie anterior fiagella also become 

 very adhesive and fuse in one short protoplasmic rod which continues 

 to beat and may fuse laterally with the cytoplasm or accumulate a 

 mass of adherent particles. The tip of the axostyle might be called 

 an organ of fixation in this accidental or casual sense but not in a 

 normal and essential one. 



It was only after long observation that we were convinced that the 

 true function of the axostyle is motor, but having once seen it in full 

 motor activity, all doubt as to its function is at once dispelled. It is 

 not merely a rigid elastic body, subject to passive curvature by the 

 constraint of contracting cytoplasm about it. It is rather a powerful 

 motor organ which comes into function when the animal is on a sub- 

 strate, and doubtless plays an impoitant part in the life of the organ- 

 ism in the mucus of the intestinal surface. As is well known the 

 organisms penetrate the crypts and Lieberkuhn's glands, and division 

 stages are to be sought in smears from the wall rather than in foecal 

 contents. The intestinal surface with its coating of glandular secre- 

 tion and the proteid-rich chyme which becomes ever flenser as its 

 soluble proteids diffuse through this intestinal wall, constitute the 

 medium most favorable for the growth and division of these flagellates. 

 The axostyle is an organ for locomotion on the intestinal surface and 

 in the viscous medium immediately covering it. 



One may watch the free-swimming stages for days and never see 

 the motor activity of this organelle which is held in a rigid axial posi- 

 tion thus giving emphasis to the skeletal interpretation. Nor is it 

 to be seen in culture slides which have been made for even a short 

 time, since individuals accumulate on the substrate as they become 

 adhesive and moribund, and such changes in the axostyle as occur in 

 these individuals are slow and far from characteristic. It is best seen 

 in freshly made slides with little fluid prepared directly from the fresh 

 mucous surface. Search of such a preparation will usually reveal 

 some individuals in intense axostylar activity. These are usually 

 somewhat rounded up (PI. 1, Fig. 10) and are often of the larger size. 

 They are on the surface of the glass with fiagella and undulating 

 membrane in full activity. In addition to this the axostyle itself 

 keeps up a vigorous lashing from side to side, sometimes constant, 

 sometimes intermittent, changing its position actively as a stout 

 flagellum from one side to the other, bending and curving as it lashes 

 a))out (PI. 1, Figs. 8, 9), now parallel to the membrane and now away 

 from it, with constant readjustments of the vacuoles among which it 

 moves. It is impossible to say that the point of emergence from the 



