ACNIDOSPORIDIA, SARCOSPORIDIA 639 



isms for many years. Spindler and Zimmerman (1945) placed asepti- 

 cally ruptured cysts of Sarcocystis miescheriana (p. 640) of pigs in 

 sterile dextrose solution and kept the preparations at 37°C. for 24 

 hours and then at room temperature. In from a few days to two 

 weeks, the "spores" budded off minute, coccoid bodies which de- 

 veloped into septate mycelia with vertical hyphae bearing spores, a 

 typical feature of the development of a fungus belonging to Asper- 

 gillus. When the conidia from the cultures were injected into or fed 

 to 50 young pigs, 25 showed at necropsy four to six months after the 

 injection or ingestion of the conidia, typical Sarcocystis cysts in the 

 muscles, while the controls remained free from infection. Cultures 

 made from the mature cysts in these pigs, developed a fungus like 

 that which had been injected. Pigs, rats and mice which fed on the 

 cysts, passed faeces and urine containing yeast-like bodies which de- 

 veloped in cultures into a fungus like that which was originally 

 cultured. Spindler 's (1947) further study revealed that in the sarco- 

 sporidian cysts of sheep and duck, the strands present within the 

 cysts were none other than the connective tissues of the host and the 

 compartments contained a network of jointed hypha-like structures, 

 and the spores appeared to be exogenous growths on the jointed 

 hypha-like structures; and each spore was capable of budding out an- 

 other spore from its free end. Spindler concludes from these observa- 

 tions that Sarcocystis of pigs, sheep and ducks are fungi, related to 

 Aspergillus. This view will explain reasonably well the difficulties 

 encountered in relation to Sarcosporidia; namely, the unknown life 

 cycle, lack of a protective membrane of the "spore," the absence of a 

 vector, and the common occurrence among herbivorous animals. 



Genus Sarcocystis Lankester. In the muscles of higher vertebrates. 

 Many species have been reported by various workers from mammals, 

 birds and reptiles on the basis of difference in host species. Species 

 (Babudieri, 1932). 



S. lindemanni (Rivolta). A few cases of Sarcocystis infection have 

 been reported from man in muscle cells of larynx (Baraban and 

 St. Remy), of biceps and tongue (Darling), of heart (Manifold), 

 of breast (Vasudevan), etc. There seem to be dimensional dis- 

 crepancies of organisms observed by different investigators. The di- 

 mensions of parasitic masses and of spores are as follows : Parasites 

 1.6 mm. by 170m and banana-shaped spores 8-9/z long (Baraban and 

 St. Remy) ; parasites 84ju by 27m and spores 4.25m by 1.75m (Darling) ; 

 parasites spherical, 500/* in diameter and spores over 10m long 

 (Manifold); parasites 5.3 cm. by 320m and spores 8.33m by 1.6m 

 (Vasudevan). The parasitic masses are oval to spindle in form and 



