THE PARASITES OF THE TERMITES. 439 



contents of the body, and assumes an oval or spherical shape, while the nucleus 

 becomes more distinct, and the undulating cord remains more or less persistent, as 

 seen in Fig. 13. 



Pyrsonympha commonly measures from 0.1 mm. long by 0.03 to 0.04 mm. wide 

 at the broader part, to 0.15 mm. long by about the same width. The longest 

 individual measured was 0.16 mm. long by 0.033 mm. wide. The nucleus meas- 

 ures 0.016 mm. in diameter, or in oval form 0.024 mm. by 0.012 mm. The 

 screw-like nonciliated forms, such as represented in Figs. 8-12, commonly range 

 from 0.075 mm. long by 0.015 mm. wide to 0.12 mm. long by 0.015 to 0.025 mm. 

 broad ; but often equal the others in size. Distinctly ciliated individuals, elon- 

 gated and fusiform, measured 0.075 mm. to 0.09 mm. long by 0.009 ram. to 0.012 

 mm. wide; and the clavate forms 0.06 mm. to 0.075 mm. long by 0.018 mm. i6 

 0.024 mm. wide. 



Pyrsonympha, though usually observed in a stationary position while it bends 

 and unbends, or writhes from side to side, may sometimes be seen moving about 

 in a slow, shuffling manner. Though it appears to take solid food, I was unable 

 to detect the mode of its entrance. At no time did I detect within the animal 

 distinct vacuoles or a contractile vesicle. 



The animal I take to be a ciliated Infusorian, though in many individuals, 

 perhaps in a particular stage of life, the oils appear to be absent. 



DINENYMPHA. 

 Dine, whirl ; numpha, nymph. 



DiNENTMPHA GRACILIS. Plate 52, Figs. 18-26. 



Proc. Acad. Nat. Sci. Philad., 187Y, 149. 



To the parasitic community of our Termite belongs the animal above named. 

 It is a ciliated Infusorian, probably related with the familiar genus Opalina, 

 though, unlike this, and like its associates, it appears to swallow solid food. Since 

 I have had the opportunity of observing ciliated forms of Pyrsonympha, I have 

 suspected that perhaps this also is only a younger stage of the former. The 

 body is a simple band with tapering extremities and pointed ends. It is longi- 

 tudinally striated, and is translucent, pale, and indistinctly granular, without a 

 clear differentiation into endosarc and ectosarc. Commonly the central portion 

 of the body contains variable proportions of coarse granules, and some irregular 

 particles probably of the nature of food, and seemingly minute fragments of wood- 

 fibre derived from the food of the Termite. Not unfrequently one or several 



