THE* PARASITES OF THE TERMITES. 433 



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When Trichonympha curls its head into a helix, the three ranks of cils above 

 described, appear to diverge in vortices from the inflection of the head, as I have 

 attempted to represent in Figs. 6, 8. 



The fourth rank of cils, the longest of all the series, springing from the 

 head, fold backward in a spiral direction, closely envelop the body, and extend 

 beyond its extremity in a twisted fasciculus with divergent ends. (See Figs. 1-3, 

 5—10.) These cils ordinarily appear to be motionless, but sometimes show a dis- 

 position to untwist and open outwardly. Usually they extend back of the body 

 much farther than the third rank of cils, but in the varied movements of the ani- 

 mal in extreme shortening the latter may reach even beyond the former, as seen 

 in Figs. 3, 8. 



When Trichonympha is viewed on end, so as to appear circular in outline, its 

 long cils diverge more or less uniformly all round in a tangential manner, and 

 recall to mind a similar view of the peristome of a vorticella. At times in the 

 same view the cils appear to diverge in several groups, and converge towards the 

 ends, as represented in Fig. 4. ■ 



In its natural position Trichonympha may be detected amidst the dense con- 

 course of its associates gliding through and displacing them as it advances. As 

 usually observed upon the object glass of the microscope it remains nearly or quite 

 stationary in position, though it may also frequently be seen advancing in a slow, 

 shuffling manner, shouldering its way, as it were, through the crowd of parasites 

 surrounding it. While it remains stationary in position it is otherwise briskly in 

 motion. The head is more active than the body, continually elongating and 

 shortening, and directing or bending its apex from side to side, or rolling it back- 

 ward upon itself into a helix, now in one and then in an opposite direction. The 

 body also elongates or shortens, becoming narrower or wider, or it widens at the 

 base and abruptly tapers to either a pointed or more or less blunt extremity ; or 

 it assumes an oval form of variable length and breadth, or it may become quickly 

 incurved on one side, or make a half twist upon itself. The shorter cils wave 

 incessantly outwardly, while the longer ones are constantly rising and falling in a 

 somewhat rhythmical manner. 



Some individuals of Trichonympha undergo dissolution in the ordinary liquids 

 of examination* almost immediately after being discharged from their natural 

 habitation, while others remain comparatively unchanged for variable periods 

 extending from a few minutes to the whole day. As the animal weakens it 



* I have usually employed for the examination of the Termite parasites neutral salt solution, aqueous humor 

 of the eye, and diluted albumen of the egg. 

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