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REPORT OF THE COMMISSIONERS OF 



and minutely lobed. The mass of protoplasm segregates into eight small spheres 

 which are not confined by a membrane. The method of formation of these 

 reproductive bodies could not be determined owing to the extremely minute size 



although various stages were seen, 

 and it was conclusively proved that 

 the groups of eight spheres were 

 derived from single spores. Each 

 sporozoite at this stage measures 

 less than one half of a micron (.0001 

 inches). (Figure I, J and K.) 



A similar process of sporozoite- 

 formation was seen in the spores 

 infesting the testis where, in one of 

 the fish examined, almost every 

 spore was in some stage cf repro- 

 duction. Here also the spores were 

 found to have a capsule or cyst 

 about them. The capsules are spher- 

 ical and no larger than the long 

 axis of the spores. The protoplasm 



F.GURE i.-Agroupof spores from the testis (A to I), end from 



the intestine (J and Ki. The cyst (X) is absent in the first Segregates in a thin deeply 

 latter. Camera drawing, x 4000 diameters. . . . . . r 



staining nm about the inner side of 

 the capsule, although a single spherical mass is always left within. (Figure 2.) This 

 mass I consider homologous with the protoplasm (or possibly nucleoplasm) left over 

 after sporozoite formation in Coccidia or Gregarinida (Reliquat de differentiation). 

 The peripheral protoplasm next fragments 

 into eight spheres or sporozoites similar in all 

 respects to those from the intestinal spores. 

 The sporozoites break through the capsule 

 and collect around the outside (Figure 1, A, 

 B, C, D, E, H, I), while empty spore cysts are 

 often seen with minute apertures (Figure 1, 

 F, G). 



The spores and sporozoites in the intestine 

 and in the testis are apparently identical 

 with the single exception of the cyst membrane or capsule. The absence of a 

 membrane in the intestinal forms is undoubtedly due to its dissolution by the various 

 digestive fluids of the alimentary tract, while in the testis there are no such solvents, 



Figure 2.— A group of spores from the testis show- 

 ing preparatory stages in sporozoite-forma- 

 tion. Cf. Figure i. Camera drawing, x 4000 

 diameters. 



