PARASITES OF PROTOZOA 1061 



By the time the parasite reaches its full size, the nucleus of its host 

 has become greatly hypertrophied and has left its normal position. A 

 variable number of spores are produced; in one instance there were 

 only 17, but usually there are from 150 to 200 or more, located within 

 an ellipsoidal membrane 25 to 44 X 22 to 36 [j. The individual spore 

 is ellipsoidal and has a size of 2.5 to 4 [j X 2 to 3 p. The spores are 

 larger in size when their number is smaller. 



The structure of the spores (Fig. 220C-E) is the characteristic of 

 greatest interest in this organism, as nothing like it is known in any 

 other nuclear parasite, or indeed in any known parasite of Protozoa. 

 The nucleus is located at one end, and is usually relatively very large, 

 having a diameter almost equal to the width of the spore. When heavily 

 stained, or when not well fixed, it appears homogeneous, but in good 

 preparations it is resolved into closely packed granules. In the cytoplasm 

 of the spore are a variable number of granules which are relatively large 

 for cytoplasmic granules. These stain intensely with hematoxylin, and 

 possibly are volutin, though no tests could be made to support that 

 view. The cytoplasmic granules are often arranged in an equatorial 

 ring (Fig. 220D), which appears solid in some preparations. Some- 

 times there are no granules outside of the nucleus except in this ring; 

 at the other extreme, the ring constitutes the margin of a solid hemi- 

 spherical mass of granules, which occupies all the area at its end of 

 the spore (Fig. 220E). Between these extremes are conditions in which, 

 in addition to the ring, there are only a few granules at the periphery 

 of the hemispherical area, or more abundant granules in a peripheral, 

 semicircular row at right angles to the ring (Fig. 220C). 



At the periphery of the mass of mature spores of the hyperparasite 

 from Procryptotermes sp., there is constantly present a single, apparently 

 crystalloid body (Fig. 220B). In different parasites this body is rela- 

 tively uniform in size and shape; and it is generally so located as to 

 cause a protrusion of the membrane. It has the form of a conventional 

 diamond, and stains deeply with Heidenhain's iron-hematoxylin but not 

 with Delafield's hematoxylin. It is unlikely that it is to be regarded as 

 residual chromatin. 



What seems to be a second parasite (Fig. 220G, H) of the nucleus 

 of Trichonympha occurred in from 70 to almost 100 percent of the 

 hypermastigote in certain preparations from the Madagascar Procrypto- 



