434 THE PARASITES OF THE TERMITES. 



assumes a symmetrical quiescent form and the longer oils cease movement, while 

 the shorter ones will still retain their activity. When it dies it becomes spherical, 

 and the contents break up into clear vesicles mingled with more defined granules; 

 and the contents of the nucleus shrink from its apparent wall. 



Trichonympha commonly ranges from 0.075 to 0.09 mm. in length by 0.035 to 

 0.045 mm. in breadth. Large individuals in active movements may elongate to 

 0.115 mm. by 0.03 mm. in breadth, and the same by contraction, together with 

 depression of the head may shorten to 0.06 mm. and widen to 0.05 mm. Indi- 

 viduals in an extreme state of shortening and proportionate widening, as often 

 seen, when the animals are first observed, measured 0.036 mm. long by 0.051 mm, 

 broad to 0.084 mm. long and 1.108 broad. Extreme length of an animal to the 

 end of the terminal twist of cils measured 0.135 mm. The extreme lateral spread 

 of the cils in an individual reached 0.24 mm. The central nucleus of Tricho- 

 nympha is from 0.012 mm. to 0.015 mm. in diameter. 



Among the tumultuous crowd of Termite parasites there are many which I 

 have suspected to pertain to immature stages of Trichonympha, though I have not 

 been able to verify the suspicion. The young, as I suppose them to be, present 

 considerable variety in size and shape. Individuals of the kind are represented 

 in Figs. 12-21, though it is difficult to obtain satisfactory views of their form and 

 structure, partly on account of their delicacy, lively movements, and thick invest- 

 ment of cils, and partly from their quickly undergoing change of shape and dis- 

 solution. 



The smallest individuals thus attributed to Trichonympha are spherical, 

 ovoidal, or pyriforra, 0.009 mm. to 0.012 mm. in diameter, or about as long as the 

 latter measurement, and as broad as the former. Larger individuals of elliptical 

 form, narrowing in front and obtusely rounded or sometimes truncate behind, 

 measure from 0.035 mm. to 0.045 mm. in length with little more breadth than the 

 smaller ones. The greater number of immature individuals are fusiform with the 

 anterior extremity somewhat produced and mammilliform, or it may be more 

 conical and pointed, while the posterior extremity is acute, or not unfrequently 

 more or less prolonged into a caudate appendage of variable shape. These forms 

 range from 0.03 mm. to 0.055 mm. in length by 0.015 mm. in breadth; but occa- 

 sionally they range from the latter length to 0.09 mm., and from the latter breadth 

 to 0.018 mm. Rarely some fusiform individuals were observed ranging from 0.1 

 mm. long by 0.02 mm. wide to 0.16 mm. long and attenuated to 0.012 mm. wide. 



The supposed immature Trichonymphce do not exhibit the conspicuous division 

 into two parts, nor the distinctness of structure presented by the perfect animal. 



