NOSEMA. 355 



By addition of weak acetic acid or iodine water the movement 

 within the spore is accentuated and results in the extrusion 

 of the polar filament. The detached filaments are dehcate 

 threads, sometimes nodular. The filament issues through 

 the pore of the sporocyst and, as it breaks ofi", the amoebula 

 emerges through the pore. In stained preparations the 

 amoebulse are seen as minute bodies with irregular outhne, 

 suggesting the possession of pseudopodial movement during 

 life. The planont is a minute globular organism ; when 

 active its movements are fairly rapid, a blunt pseudopodium 

 being extruded in one direction only. Division takes place 

 by binary fission. Planonts collect into groups or colonies 

 of varying numbers of individuals. 



After penetration into a cell the mobile planont becomes the 

 oval meront. The meront is larger than the previous phases, 

 has homogeneous cytoplasm, with a centrally or excentricaUy 

 placed refractile spot. It forms generations of merozoites, 

 either by binary fission forming chain-like groups (fig. 175, D) 

 or by multiple fission forming small clusters of cells (fig. 175, E). 

 The final product of the division of the meront is a sporont 

 which forms the sporocyst, polar capsule, and polar filament. 

 The spore is recognized by its egg-shaped outHne and by the 

 presence of one or two vacuoles at either pole. In stained 

 films can be seen, in addition, a cystic wall containing two 

 parietal nuclei, a polar capsule and polar filament, and the 

 sporoplasm. The polar capsule is a hollow pear-shaped body 

 containing a spirally twisted thread, and a capsulogenous 

 nucleus situated at its broader end. The sporoplasm contains 

 a, single nucleus and no vacuoles. 



Dimensions. — Planont 0-75-1 /a; spore up to 1-5/z, in length; 

 length of extruded filament 25 ^u,. 



Remarks. — Heavily infected larvae are dark and mottled 

 in appearance, owing to the presence of the Nosema, and are 

 thus easily distinguished. 



Korke (1916) described the species as N. pulicis, probably 

 in ignorance of the fact that NoUer (1912, 1914) had already 

 described a species of that name from the dog-flea in Germany. 

 As the dimensions of the spores are quite different in the 

 two forms, Kudo (1924) has given the name iV. denocephah 

 to the Indian form. 



Habitat. — Digestive tract of the larvae of the dog-flea, 

 named by Korke Ctenocephalus felis (Bouche), probably 

 Ctenocephalus canis (Curtis) : Punjab, KasauH. 



2a2 



