DEVELOPMENT OF A MYXOSPORIDIAN 349 



space separates the gemmule from the surrounding endoplasm. 

 This is no doubt due to shrinkage and indicates that the gem- 

 mule Hes in a distinct cavity formed in the endoplasm of the 

 mother trophozoite. In dried smears stained by the Giemsa 

 method the cytoplasm of the gemmules stains a light blue while 

 the cytoplasm of the mother trophozoite stains a light red. In 

 the younger stages the nuclei of the gemmules contain no nucleoli, 

 but by the time the 8-nucleate stage is reached there is usually 

 a well defined nucleolus in each nucleus. There may be several 

 gemmules present at the same time in a trophozoite as shown 

 in figure 71 where there are nine, and trophozoites with even 

 larger numbers are not rare. 



The 8-nucleate state is usually as far as the gemmules develop 

 within the mother trophozoite. They now make their way 

 to the periphery (fig. 69), thence to the exterior by rupture of 

 the ectoplasmic layer. I have several times observed the escape 

 of gemmules from living trophozoites (fig. 60). Moreover, 

 gemmules which have evidently just emerged from the mother 

 trophozoites are common. 



After the gemmules become free, four of the nuclei enlarge to 

 form vegetative nuclei, while the other four become surrounded 

 by a differentiated area of cytoplasm and develop into generative 

 cells (figs. 72 and 73). 



Occasionally the gemmules may be retained in the body of the 

 mother trophozoite for a longer time. In such cases they in- 

 crease in size and begin to develop in the same way as those 

 which have become free (figs. 62, 74 and 75). The cytoplasm 

 loses its dense, finely granular structure and no longer stains 

 more deeply with plasma stains except near the center, where 

 the denser material may persist for some time. Around the 

 periphery the cytoplasm becomes vacuolated and exhibits a char- 

 acteristic radiate structure (fig. 74). The nuclei increase in 

 number by mitotic division and become differentiated into 

 vegetative and generative as in the free forms. 



This method of reproduction obviously furnishes a means for 

 the rapid increase of the parasites within the host. Apparently 

 the gemmules always develop into the large form of tropho- 



