Ill [ 175 ] 



moths, the latter may ])e again used to profit. In the year 1824, he raised 

 many worms from eggs the produce of a sixth coupling, which were 

 fully equal to those produced from eggs at the first. The union conti- 

 nued never less than from twenty to twenty-four hours. The inale, 

 after a sixth union, appeared as lively and as brisk as at first, but he 

 had no more females. The eggs from even a thirteenth union of the 

 same male with different females, had all the characters of those of the 

 best quality. In these cases the disunion of the pair was, moreover, 

 never spontaneous, hut always required to be effected by the hands."' 

 Before separating the sexes, prepare, in a cool, dry, airj- chamber, 

 the linen on which the moth is to deposite its eggs. The following is 

 the manner in which the cloth must be arranged: 



At the bottom of the tressel, plate 1, fig. 5, which must be about 

 four feet seven inches high, and three feet eight inches long, place, ho- 

 rizontally, on each side of the length, two boards, so arranged that 

 one of their sides should be nailed to the tressel, about five inches and 

 a half high above the ground, and that the other side of the board shall 

 be a little higher, and project outwards, Upon the tressel lay a cloth, 

 so that it may haug equally on each side. The ends of the cloth must 

 cover the boards below. The more perpendicular the lateral parts of 

 the tressel are, the less soiled will be the cloth, by the evacuation of 

 the liquid that conies from the moths. The mothsUvhich have been 

 united six hours, are then to be gently separated, the females placed 

 on the frame, and carried to the tressel and placed on the cloth, one 

 over another, beginning at the top, and going downwards. Note the 

 time at which the moths are placed on the cloth, taking care to keep 

 those which are placed afterwards separate, to avoid confusion. The 

 females that have had a virgin mate must be treated in the same man- 

 ner as those which have been united v,nth one that had been coupled 

 previously five hours. The females should be left on the cloth 36 or 

 40 hours, without being touched. At this time, if it be observed that 

 the linen has not been well stocked with eggs, other females must be 

 placed on it, in order that the eggs may be equally distributed. When 

 the heat of the room is 77° or 79°, or when at 63° or 65°, the egsjs will 

 be yellow, that is, unimpregnated, or of a reddish color, that is, im- 

 perfectly impregnated, and will not produce worms. The temperature 

 of the room must therefore be kept between these extrem.es. Some- 

 times a fe.male moth will escape from its mate before impregnation, 

 and produce man}^ useless eggs. Mr. Swayne remarks, " that he had 

 a cocoon of an orange color given to him, the moth of which happen- 

 ed to be a female. From this, by coupling with a straw-colored mate, 

 were propagated all that he had of an orange color. Hence he con- 

 cludes, that the color of the silk depends chiefly upon the female."! 



* Essai sur L'llistoire, &c. p. 69. Should others have the same success as this au- 

 thor, many cocoons containing males wliicii arc preserved for seed, nia}' be used for 

 winding, and comparatively a smaller number than ft-males be kept for coupling. He 

 thinks that one-sixteenth part of males, in a parcfl of cocoons, would be sufficient. 

 The experiment of repeated unions siiotild be made. 



f Trans. Soc. Ai-U, London, vol. 7, p. 144: 



