51 



The worms when first hatched take 56,626 to make 

 an ounce; after the first moulting 3,840 are sufJti- 

 cient to make up that weight ; thus in six days the 

 worm increases fourteen times its own weight : at 

 first it is but the twelfth of an inch long. On the 

 eighth day it becomes torpid. 



On the 9th day, the worm becomes of a light gray, 

 the hair hardly to be perceived by the naked eye, 

 and becomes shorter; the muzzle, which, in the 

 first age, was very black, har.J and scaly, becomes 

 immediately upon moulting white and soft; but af- 

 terwards, again grows shining and black as 

 before. As the insect grows older, at each moul- 

 ting, its muzzle hardens ; because it needs to saw 

 and bite larger and older leaves. Its size is in- 

 creased to half an inch, and part become roused on 

 this day and part on the 10th. On the 14th day 

 they go into torpor again; just preceding this state, 

 the insect seeks free space to slumber in, rearing its 

 head upwards. When on the point of sinking into 

 torpor, they completely void all excrementitious 

 matter, and there remains in their intestinal tube a 

 yellow lymph alone. When the worms prepare for 

 the 3d and 4th moulting, the ventilators must be 

 opened. 



On the 15th day, the worms begin to rouse, and 

 thus accomplish the third agei The head and body 

 are much enlarged since the casting of the skin. 



On the 20th day, the worms become torpid : rouse 

 on the 22d day. After this moulting, they are of a 

 darker color, grayish with a red cast, but continue to 

 whiten. 



By the 30th day of their being fed, the worms be- 

 gin to advance towards maturity, which may be 

 perceived by their yellow color, which increases 

 from ring to ring. Their backs begin to shine, and 

 the rings lose their dark green color. The ad- 

 vance to maturity is also evinced by diminution of 

 bulk, and by their seeking to fix themselves on the 

 edge of the shelves or hurdles, to void Ihe sub- 

 stances with which they are loaded. When these 

 signs are apparent, the offal and excrement must be 

 cleaned off' and removed, light fires raised, and the 

 apartment fumigated. 



On the 30th day, the yellow hue of the silk 

 worms grows deeper, their backs shine more, and 

 in some, the rings assume a golden appearance, the 

 uiuzzle becomes a brighter red. 



On the 32d day, they generally attain perfection, 

 which may be known by the following indications : 



1. When on putting leaves on the shelves the 

 worms get on them without eating them. 



2. They appear of a whitish yellow, transparent 

 color. 



3. The worms get upon the edges and move 

 slowly along, instinct urging them to seek a change 

 of place. 



4. Their rings draw in, and their greenish color 

 becomes a deep golden hue. 



Their skins become wrinkled about the neck, and 

 their bodies have more softness to the touch than 

 heretofore, and feel like soft dough. 



6. In looking through the worm, the whole body, 

 it will be seen, has assumed the transparency of a 

 ripe yellow plum. 



When these signs are manifest, it is time for them 

 to mount. 



VARIOUS QUALITIES OP COCOONS, 



Dandolo says the cocoons may be divided into two 

 general heads or classes ; the white and the yellow. In 

 the yellow we meet with all the shades from a bright 

 yellow, diminishing, at last, to while : some few are a 

 pale green. 



There are he says nine different qualities, which 

 he thus describes : 



1. The good cocoons arc those which are brought to 

 perfection and are strong, hard, of a line grain, and but 

 little or riot at all spotted. 



2. The pointed cocoons arc those of which one of the 

 extremities rises up in t* point, uno are difficult to 

 reel, because when the thread comes round to the 

 hole, it is, of consequence, broken, and the whole con- 

 tains nothing but ends. 



3. The cacalons are a little larger than the others ; 

 yet they do not contain more silk, because their con- 

 texture is not so strong. 



4. The doupion, or double cocoons, are so called, be- 

 cause they contain two, and sometimes three worms. 

 They interlace their threads and make the silk called 

 doupion. 



5. The soufflons are imperfect cocoons, the contexture 

 of which is loose, sometimes to that degree that they 

 are transparent, and bear the same proportion to a 

 good cocoon, as a gauze to a satin. These cannot be 

 wound. 



6. The perforated cocoons are so called, because 

 they have a hole at one end ; for which reason they 

 cannot be wound. 



1. The calcined cocoons are those in which the worm, 

 after the formation of the cocoon, is attacked with a 

 sickness, which sometimes petrifies it, and at other 

 times, reduces it to a fine white powder, without in the 

 least damaging the silk. On the contrary, these co- 

 coons produce more silk than the others, because the 

 worms are lighter. They are to be distingusbed by the 

 noise the petrified worm makes when the cocoon is sha- 

 ken. 



8. The good choqueltcs consist of those cocoons m 

 which the worm dies before it is brought to per- 

 fection. They can be distinguished from the others, 

 because they do not rattle when shaken. They pro- 

 duce as fine silk as the others; but should be wound 

 separately, as they are subject to furze out, and the 

 silk is neither of as bright a color, nor so strong as the 

 rest. 



9. The bad choquelte is composed of defective cocoons, 

 spotted or rotten : many of them may be wound togeth- 

 er, but make very foul, bad silk of a blackish color. 



HOW TO JUDGE A COCOON. 



To judge whether a cocoon be good, observe if it be 

 firm and sound : if it has a firm grain, and the two 

 ends round and strong and capable of resisting pressure 

 between the thumb and the finger. The cocoons of a 

 bright yellow, yield more silk than the others, because 

 they have more gum. Pale cocoons leave less gum, 

 lose less in winding, and take a better white or pale 

 blue. 



GATHERING OF THE COCOONS. 



Strong healthy worms, in three days and half 

 from their time of moulting, will complete their cc- 

 coons, and this period may be shortened by increas- 

 ing the temperature of the apartment. On the 

 other hand their labors are prolonged by a colder 

 temperature than has been fixed, as also by feeble 

 health. Transitions from heat to cold, as well as a 

 vitiated atmosphere and sudden draughts of wind be- 

 fore the cocoons are sufficiently advanced to afford 

 them shelter, are injurious. The cocoons will be 



