152 MICKOBES, FERMENTS, AND MOULDS. 



own researches soon induced him to adopt the 

 same view. 



The pebrine microbe was long regarded as a true 

 bacterium, successively described as Bacterium bom- 

 bycis, Nosema bombycis (Fig. 72), and 

 Panistophyton ovate. Balbiani's recent 

 r\* 0^0 ^ researches tend to show that it should 

 o 9- be assigned to another group, much 

 0- ( nearer to animals, and designated 



Fig. 72. Nosema, 

 bombycis, pebrine 



microbe (x 500 SpOTozoaria. These protista, still 

 regarded as plants by many naturalists, 

 chiefly differ from bacteria by their mode of growth 

 and reproduction, in which they resemble the para- 

 sitic protozoaria, termed Psorospermia, Coccidies, and 

 Gregarinidce. 



In Sporozoaria, growth by fission, the rule in all 

 bacteria, has not been observed ; this distinction is 

 fundamental. Sporozoaria multiply by free spore- 

 formation in a mass of sarcode substance (protoplasm), 

 resulting from the encysting of the primitive corpuscles 

 (mother-cells). The formation of numerous spores 

 may be observed within the mother-cells, having the 

 appearance of pseudonavicellce or spores of gregari- 

 nidseand psorospermia (parasites of vertebrate animals). 

 Balbiani forms these organisms, which are found in 

 many insects, into a small group, which he terms 

 JMicrosporidia. 



The ripe spores are the vibratile corpuscles of 



