272 The Philippine Journal of Science me 



planted in a drop or two of blood, whole or defibrinated, smeared 

 on an agar slant, there ensues a course of development some 

 features of which are not to be seen under other conditions. 



The homogeneous basic forms, which are slightly blue after 

 Giemsa's stain, enlarge somewhat and stain more deeply. Some- 

 times the entire-cell form becomes prominent (fig. 18). 



Spore- granules. — Within the "nuclear" body of the enlarged 

 parasite, whether it be endowed with protoplasm or not, there 

 develop a few extremely small, lighter points, due to the earliest 

 appearance of the small hyaline spore-granules (fig. 19, upper 

 parasite). The color of the cell now becomes distinctly purplish 

 in Giemsa-stained preparations, more closely resembling a 

 degenerating leucocyte nucleus. The spore-granules enlarge and 

 become more numerous (fig. 19, lower parasite), appearing as 

 minute, round, oval, and rod-shaped bodies. 



The outline of the containing cell soon becomes indefinite, and 

 the whole appears soft (fig. 20). Smears occasionally show 

 groups of the spore-granules that are compactly massed (fig. 

 21). When liberated the spore-granules usually become indis- 

 tinguishable in smear preparations, though they may be present 

 in large numbers (fig. 22). After Gram's stain they retain the 

 safranine coimterstain and may be tentatively identified by their 

 higher refraction. Giemsa's stain does not color them as a 

 rule. After Loefl'ler's blue the larger are often easily discern- 

 ible by their clear, light, refractile blue. 



The formation of these spore-granules seems an extremely 

 simple process. There is no definite segmentation, nor is there 

 any apparent mechanism governing the number or size. They 

 appear much as might crystals separating out of a protoplasmic 

 mass and occur only within the nucleus until this is no longer 

 demarked. They have not been observed in the tissue sections. 

 While they seem to be produced for multiplication only, compara- 

 tively very few are capable of development under the conditions 

 obtaining. In the free blood of these cultures a few (as in the 

 center of fig. 22) enlarged into typical basic forms. In occa- 

 sional cultures the viable granules, before developing into the 

 leucocytelike bodies and cells, become rod-shaped or slightly 

 curved, often appearing as small bacilli (fig. 23). Prominent in 

 most of these half -grown and larger organisms is the appearance 

 of one or two small metachromatic granules, often placed as 

 bars across the organism. This was the first form to be re- 

 cognized as developing in the cultures and at first was misunder- 

 stood. The more mature cells are usually oval (figs. 24 and 25), 

 and after Giemsa's stain the protoplasm presents a clear. 



