16 THE CULTUEE OF THE MULBERRY SILKWORM. 



incubator, such as is used to hatch chickens, would be more conven- 

 ient, but would cost more. 



The whitening of the eggs denotes the near approach of the hatch- 

 ing. Double pieces of tulle or sheets of perforated paper sprinkled 

 over with finely cut-up white mulberry leaves should then be lightly 

 placed over the eggs to allow the outward passage of the worms as 

 soon as hatched. The object in employing two pieces of tulle or 

 paper is to prevent the unhatched eggs which cling to the sheet from 

 being removed with the newborn worms. This process must be 

 repeated daily during the hatching, the second sheet always being 

 renewed. 



The duration of the hatching varies from three to five da} r s, the eggs 

 hatching about as follows: During the first da} r , 5 per cent; during 

 the second, 33 per cent; during the third, 50 per cent; during the fourth, 

 5 per cent; during the fifth, 7 per cent. 



Twenty-five grams of eggs will give about 17 grams of worms. In 

 small rearings most cultivators raise only the worms that are hatched 

 on the second and third days, to avoid the necessity of forming too 

 many classes. The worms must be classed according to the date of 

 birth, and the insignficant number hatched on the first and last days 

 scarcely compensate for the trouble of rearing them. Different races 

 must also be reared separately. 



Where several in one neighborhood are engaged in silk culture it 

 greatly reduces the cost to have all the eggs hatched in one incubator. 

 The person best acquainted with silk culture can undertake the incu- 

 bation, and distribute the young worms on the second or third days to 

 those who are to rear them. This is the plan adopted among the Italian 

 peasantry, the wife of the supervising farmer hatching the eggs for 

 whole villages. 



THE REARING OF SILKWORMS. 



Before entering into the details of a rearing some general directions 

 must be given concerning the rearing room — the heating, ventilation, 

 and disinfection. 



GENERAL DIRECTIONS. 



The place chosen for a rearing should be relatively high, and not 

 exposed to malaria or bad odors, and mulberry trees should grow 

 around it. Any room that can be properly heated and ventilated will 

 answer the purpose. An open fireplace is the best means of heating, 

 but is expensive, as much of the heat is lost. Hot-water pipes, such 

 as are used to heat a greenhouse, are good for a building specially 

 built for silkworm rearing. Iron stoves should not be used, unless 

 placed in an adjoining room with communicating pipes. Never employ 

 charcoal as fuel. 



