ON AILANTHINE. 267 



Alsace, who have made use of ailanthus silk. M. Schlumberger 

 has found the cocoon very easy to card and spin ; the thread ob- 

 tained is less brilliant, strong and rough; it left no residue, not more 

 than in combing the thread. It is a most excellent stuff for use 

 in all manufactures where burre is employed. The cocoons are 

 easily cleaned and they will take a good dye. This culture, made 

 on a great scale, will furnish in abundance a liner and stronger 

 floss than the mulberry silk-worm. The worm remains in the 

 cocoon in the chrysalis condition for from twenty-six to thirty 

 days, at which time the moth makes its appearance coming quickly 

 and easily through the valvular opening at the extremity of the 

 cocoon. At this time its wings are moist, soft, and folded up ; 

 and naturally upon emerging from the cocoon it seizes hold of the 

 lower part of it, thus allowing its large wings to drop, become un- 

 folded and stiffen. If this precaution is not taken when the moths 

 are allowed to exit artificially, their wings never expand but remain 

 crumpled up, the moth never regaining much activity with its 

 wings in this state, and seldom connecting itself with the opposite 

 sex. In rearing these moths therefore, it is of consequence to 

 observe that upon their exit from the cocoon they have some sub- 

 stance on which they can climb up and allow their wings to hang- 

 down and become expanded. 



The moths have been long familiar to us, in collections of 

 Chinese Butterflies, brought to this country. It is large, the ex- 

 pansion of its wings being about five inches ; the head and an- 

 tennae are greyish brown, the latter strongly pectinated ; thorax 

 and abdomen lighter grey, wings with a broad transverse light- 

 coloured band near the middle, the space within which (forming 

 nearly an equilateral triangle) is brownish grey, and that without 

 ash colour, running into brownish grey at the margins of the wings, 

 just within the margins there are two narrow, brown streaks run- 

 ning parallel with them, somewhat interrupted before reaching a 

 black spot near the apex of the superior wings ; this spot is sur- 

 mounted by a white crescent, and a zizgag white line runs from it 

 to the tip. The basal portion of the superior wings is traversed 

 by an ash-coloured bar commencing on the posterior edges next the 

 shoulder, and after continuing in nearly a straight line for about 

 half an inch is suddenly deflected and terminates on the anterior 

 margin, between this bar and the transverse scapular line there is 

 a pale longitudinal spot surrounded with black. The under wings 

 likewise bear a similar spot but more crescent-shaped, and towards 



