MOTIONS OF INSECTS. 295 



stalks of the common spurrey (Sagina arvensis\ upon 

 my touching this stalk, whirled round several times with 

 astonishing rapidity. The chrysalis of a scarce moth 

 (Hypogymna dispar] when touched turns round with 

 great quickness ; but, as if fearful of breaking the thread 

 by which it is suspended by constantly twisting it in one 

 direction, it performs its gyrations alternately from left 

 to right, and from right to left a . Generally speaking, 

 quiescent pupae when disturbed show that they have life, 

 by giving their abdomen violent contortions. 



But the most extraordinary motion of pupae is jump- 

 ing. In the year 1810 I received an account from a 

 very intelligent young lady, who collected and studied 

 insects with more than common ardour and ability, that 

 a friend had brought her a chrysalis endued with this 

 faculty. It was scarcely a quarter of an inch in length ; 

 of an oval form; its colour was a sem transparent brown, 

 with a white opake band round the middle. It was 

 found attached, by one end, to the leaf of a bramble. It 

 repeatedly jumped out of an open pill-box that was an 

 inch in height. When put into a drawer in which some 

 other insects were impaled, it skipped from side to side, 

 passing over their backs for nearly a quarter of an hour 

 with surprising agility. Its mode of springing seemed 

 to be by balancing itself upon one extremity of its case. 

 About the end of October one end of the case grew 

 black, and from that time the motibn ceased; and about 

 the middle of April, in the following year, a very mi- 

 nute ichneumon made its appearance by a hole it had 

 made at the opposite end. Some time after I had re- 

 ceived this history, I happened to have occasion to look 

 11 Dumeril, Trait. Element, ii. 49. n. -603. 



