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3. Preservation of cocoons intended for seed. 



• Experience shows that where the temperature of the room Is above 

 78°, the transition of the chrysalis to the moth state, would be too ra- 

 pid, and the coupling will not be productive. If below 66°, the deve- 

 lopment of the moth is tardy, which is also injurious. Damp air will 

 change it into a weak and sickly moth. The jipartment should, there- 

 fore, be kept in an even dry temperature, between 66° and 73°. 

 When collected, spread the cocoons on a dry floor, or on tables, and 

 strip them clean of down or flos, to prevent the feet of the moth being 

 entangled in it when coming out: while cleaning them, all those that 

 appear to have any defect should be laid aside: this is the time, also, 

 to separate the male and female cocoons, as far as we can distinguish 

 them. 



Mr. Stephenson directs the selection of an equal number of males 

 and females, and to keep the cocoons of the same day's mounting se- 

 parate, that the moths may pierce them at the same time. If the good 

 cocoons, taken from the whole parcel, ^re all first mixed, and the 

 selection for those intended for breeding be made from this general 

 heap, many will be set aside, which were formed by worms that had 

 mounted upon different days, and which will be pierced by the moths 

 unequally, and hence there will not be an equal number of males and 

 females produced at the same time. This irregular appeanuice may 

 cause the loss of a great many moths or of several thousand eggs. 

 Pullein orders the choice to be made from those shelves, or arbors in 

 which the worms spun the earliest. But it is questionable, whether 

 the circumstance of early spinning, would affect the worm next season, 

 unless the temperature of the apartment in both seasons was equal. 

 Dandolo says, that the strength shown by a worm in forming a cocoon, 

 has no influence upon the fecundity of the niale, nor upon the quality 

 of the eggs. Cocoons of various tenuity and shapes, have equall)^ af- 

 forded him large quantities of well-impregnated eggs. Healthy worms, 

 of equal weights, have given cocoons which varied in weight. 



When the selection has been made, the sorted cocoons must be put on 

 tables, in layers of about two inches, allowing the air to pass freely 

 through them, that it may not'be necessary to stir them frequently; 

 but it is beneficial to stir them round once a day if the air be moist. 

 When the seed cocoons are not very numerous, they may be strung 

 upon threads and hung against a wall, or suspended from a beam. 

 Just so much of the middle of the cocoon is to be pierced with a nee- 

 dle as is sufficient to attach it to the thread. The middle is chosen, 

 because it cannot be ascertained at which end the moth will pierce the 

 cocoon. Place a male and female, alternatel)'-, upon tlie thread, that 

 they may be near each other when they come out.* 



If the heat of the apartment is above 73°, every, method of dimin- 

 Ing the heat should be tried; such as keeping all apertures to the sun- 

 ny sides carefully closed, to cause thorough draughts of'air to dry the 



■ Stnphen<;nii, 



