81 



Fig. 14.— Worm emaciated by gattine 

 after the fourth molt. (Redrawn 

 from. Nenci. ) 



on the first little twigs and distending themselves as though asleep, 

 sometimes with the head turned towards the base. Again, especially 

 in case of gattine, the worm wanders restlessly here and there, seek- 

 ing as it were power to eject the silky matter, but too impotent to do 

 more than throw out a scanty thread to 

 weave a web or veil of a cocoon, in which 

 it generally falls and dies. 



Eggs free from disease and capable of 

 resistance to disease are the prime requisite 

 in guarding against flacherie and gattine. 

 The moment some deaths are noticed, pro- 

 ceed as follows: (1) Change beds immediately, briskly shaking the 

 worms; (2) place the worms on disinfected shelves; (3) burn the dis- 

 eased and su-spected worms that do not mount on fresh beds; (4) if 

 possible move the whole rearing to another room previously aired and 

 disinfected, and also aired after disinfection; (5) do not feed during the 

 three or four hours in which the change is being made; (6) keep up a 

 little wood smoke in the room; (7) give a few scanty meals of light 

 leaf; and (8) diminish the temperature a little. 



CALCINO, OB MTJSCARDINE. 



This disease, at first, has no visible appearance, but by degrees the 

 vitality of the worm is impaired, and it eats and moves slowly. The 

 body turns rose-colored or red, beginning with the stigmates, and then 

 contracts and loses its elasticity, after which the worm stands still as 

 though paralyzed, and finally dies 20 to 30 hours from the appearance 

 of the first symptoms. After death the body dries up and is covered 

 with a white efiiorescence, causing it to look like 

 a stick of white chalk (fig. 15) ; hence the name of 

 the disease. 



Calcino is caused by a mold or minute fungus. 

 There are two varieties of this fungus: Botrytis 

 hassiana and B. tenella. They both attack the 

 worm in the same way The spores of the mold 

 by chance get on the body of the worm when it is 

 in a molting condition, and there take root, pene- 

 trating below the skin. The thread-like mycelium 

 ramifies until it fills the entire body. Later some 

 of the branches fructify on the surface, and the 

 fruit bursting envelops the worm with innumer- 

 able spores resembling a white powder. 

 Each spore is capable of settling on a molting worm and giving it 

 calcino, hence the necessity of taking steps to avoid contagion. Cal- 

 cino is more contagious than other silkworm diseases. Darkness, 

 stagnant air, dirt, warmth, and moisture are the five things that favor 

 mold, and calcino is a mold. 



166 



Fig. 15.— Calcinated worm. 

 (Redrawn from Verson 

 and Quajat.) 



