PoETEE. — Trichonympha. 



PLATE 4. 



All figures are of Pyrsonynipha vertens. 



Fig. 45. Parasites attaclied by peduncles to a hit of the intestine of the host. 

 Drawn from living specimens. X 400. 



Fig. 46. Optical section of anterior portion of a Pyrsonympha, showing the rela- 

 tion of the knob-like structure {tub.) to the flagellum on one side and 

 the peduncle on the other. X 1100. 



Fig. 47. Anterior portion of an individual, showing the nucleus and the superficial 

 muscular cords. X 1100. 



Figs. 48, 49. Nuclei in stages of division. 



Fig. 50. A very much attenuated nucleus. 



Fig. 51. Surface view of a Pyrsonympha. Between the spiral muscular cords are 

 bands of granular protoplasm. The region at a is bare of all muscu- 

 lar cords. At the extreme posterior portion are several ring-like 

 markings (a?!?;.). X 400. 



Fig. 52. Cross section through the animal in the region of the nucleus. X 1100. 



Fig. 53. Optical longitudinal section of a Pyrsonympha with its nucleus in the 

 posterior half of the body. X 520. 



Fig. 54. Portion of the surface of a Pyrsonympha, greatly magnified, showing a 

 finer and a coarser set of muscular cords. The cords of the finer set 

 are surrounded by a clear homogeneous substance, while granular 

 protoplasm surrounds those of the other set. 



Fig. 55. Optical section of the Pyrsonympha represented in Figure 51. There are 

 two nuclei flattened against each other. X 400. 



