472 INFECTIVE DISEASES. 



prophylactic measures have been described in another chapter 

 (P 7). 



Fanhistophyton ovatum. (Lebert. JVosema bombycis, Micro- 

 coccus ovatus, Corpuscles du ver-d,soie). — Shining oval cocci, 2 to 3 /i 

 long, 2 /J. wide, singly and in pairs, or masses ; or rods, 2 '5 /t thick, 

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

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

 des corptiscles or JFlecksucht ; and were discovered in the organs of 

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



Metchnikoff believes that these micro-organisms are not bacteria, 

 but psorosperms. 



Flacheeie. 



Silkworms are also subject to a very destructive disease known 

 as flacherie, flaccidezza, maladie de mwts 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 atti'ibuted 

 to a streptococcus. 



Streptococcus bombycis (Jlih-ozyma bombycis, Bechamp). — 

 Oval cocci r5 /i diam., 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. 



