472 INFECTIVE DISEASES. 



prophylactic measures have been described in another chapter 



(P 7). 



Panhistophyton ovatum. (Lebert. Nosema bombycis, Micro- 

 coccus ovatus, Corpuscles du ver-a-soie). Shining oval cocci, 2 to 3 /A 

 long, 2 /A wide, singly and in pairs, or masses ; or rods, 2'5 /x, thick, 

 and twice as long. They multiply by subdivision. They were 

 experimentally proved to be the cause of pebrine, gattine, maladie 

 des corpuscles or Flecksucht ; and were discovered in the organs of 

 diseased silkworms, as well as in the pupae, moths, and eggs. 



Metchnikoff believes that these micro-organisms are not bacteria, 

 but psorosperms. 



FLACHERIE. 



Silkworms are also subject to a very destructive disease known 

 as flacherie, flaccidezza, maladie de morts blancs. The worms cease 

 feeding, die and become a putrid mass. The disease is dependent 

 upon bad hygienic conditions, and is very infectious. The cause 

 has not been determined with certainty, but it has been attributed 

 to a streptococcus. 



Streptococcus bombyeis (Mikrozyma bombycis, Bechamp). 

 Oval cocci 1'5 //. diain., singly, in pairs, and in chains. They are 

 said to be present in dust from infected localities. 



DISEASE OF CATERPILLARS. 



Forbes has described an infectious disease of the larvae of a 

 caterpillar (Picris rapce). Cocci which were found singly and in 

 masses, were regarded as the cause of the malady. 



