THE TECHNOLOGIST. [Dec. 1, 1864. 



234 ON THE NEW CHINESE SILKWORM 



tbat which separates the first change from the second. The body of 

 the caterpillar at that time is yellow, with the head, the points of the 

 segments, and the tubercles, black. It measures from eight to ten milli- 

 metres long ; and in the third age the body is from fifteen to seventeen 

 millimetres long : it is soon covered with a waxy substance, quite white, 

 intended to shield it from the rain." 



Mons. Blain has omitted to notice that at this age the tubercles grow 

 into (as it were") pyramids, or rather obelisks, each one capped with a 

 black spot, the insect presenting a more singular appearance than it 

 does at any other time. While in the greenhouse, three worms unac- 

 countably disappeared, twenty only remaining for the open-air experi- 

 ment. On Friday, 15th July, the plant was taken, with the worms 

 upon it, from the greenhouse, and placed under the Ailanthus in the 

 garden (which, as a safeguard against birds, had been netted over), and 

 the silkworms soon dispersed themselves over the tree. The change 

 from a heat of upwards of 70 deg. to a low summer temperature 

 seemed in no way to injure, but on the contrary, to invigorate them, 

 and they grew rapidly. Shortly afterwards, however, one died, ap- 

 parently in the attempt to move from one to another of the trees. The 

 changes proceeded regularly, the worms increasing wonderfully in size 

 in the course of a very few days. One, however, remained in the waxy 

 state, and seemed utterly unable to divest itself of that skin. 



Mons. Blain's description of these changes is as follows : — " In the 

 fourth age the waxy substance still exists, but the body and tubercles, 

 from white, pass little by little to green ; the head and the feet become 

 of a beautiful golden yellow, as well as the last segment. At that time 

 it attains from twenty to twenty-five millimetres. In the fifth age, the 

 green colouring becomes more decided ; the extremity of the tubercles 

 is blue ; it has on the last segment a blue border, as well as a little speck 

 of the same colour at the rise of its membranous feet. It quickly ac- 

 quires a length of from eighty to ninety millimetres ; in this condition 

 it eats less, its colouring becomes yellowish, after which it loses no time 

 in finding one or two leaflets, which it fastens firmly to the principal 

 stalk, in order to fix its cocoon." On Friday, the 2.9th of July, between 

 seven and eight o'clock in the evening, the gardener noticed that one 

 was spinning, and before morning it had covered itself up entirely. On 

 Sunday, the 31st, another began, and by two o'clock had made con- 

 siderable progress, but rain coming on prevented me observing it. 

 After this there never was a day when cocoons were not begun, and by 

 the afternoon of the 3rd of August (the last opportunity I had of seeing 

 the worms), twelve had already covered themselves up. On my return 

 home, the gardener reported to me that, in the week beginning Sunday, 

 the 14th, three died, owing, it may be supposed, to a violent hailstorm, 

 for they never seemed to thrive after it. This loss left only one remain- 

 ing to spin, the one the changes of which had been so protracted. On 

 Saturday, the 20th of August, I saw it ; it had grown to be larger than 



