Natural history of insects : comprising their architecture, transformations, senses, food, habits--collection, preservation and arrangement . ards; so thatwhen a bird put in its bill at one end of the roll, theinsect makes a ready exit at the other^ and dropsalong its thread as low as it judges convenient. We 1 SPINNtNG CATERPILLARS. 307 have seen caterpillars drop in this way from one tosix feet or more; and by means of their cable, whichthey are careful not to break, they climb back withgreat expedition to their former place. The structure of their legs is well adapted forclimbing up their s
Natural history of insects : comprising their architecture, transformations, senses, food, habits--collection, preservation and arrangement . ards; so thatwhen a bird put in its bill at one end of the roll, theinsect makes a ready exit at the other^ and dropsalong its thread as low as it judges convenient. We 1 SPINNtNG CATERPILLARS. 307 have seen caterpillars drop in this way from one tosix feet or more; and by means of their cable, whichthey are careful not to break, they climb back withgreat expedition to their former place. The structure of their legs is well adapted forclimbing up their singular rope—the six fore-legsbeing furnished with a curved claw; while the pro-legs (as they have been termed) are no less fittedfor holding them firm to the branch when they haveregained it, being constructed on the principle offorming a vacuum, like the leather sucker withwhich boys lift and drag stones. The foot of thesimilar sucker, by which it isglass, and otherwise support it-The different forms of the legand pro-leg of a spinning caterpillar are representedin the figure. common fly has aenabled to walk onself against heg and Pro-leg of a caterpillar^ greatly viagnificd. In order to understand the nature of the appa-ratus by which a caterpillar spins its silk, it is to berecollected that its whole interior structure differsfrom that of warm-blooded animals. It has, pro-perly speaking, no heart, though a long tubulardorsal vessel, which runs along the back, and pul-sates from twenty to one hundred times per minute, 308 INSECT ARCHITECTURE. has been called so by Malphigi and others: butneither Lyonnet nor Ciivier could detect any vesselissuing from it; and consequently the fluid which isanalogous to blood has no circulation. It differs alsofrom the higher orders of animals, in having nobrain, the nerves running along the body being onlyunited by little knobs, called ganglions. Anothercircumstance is, that it has no lungs, and does notbreathe by the mouth, but b
Size: 2250px × 1111px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookidnaturalhistoryof01bos, booksubjectinsects
