CERURA. 251 



" The very colours of caterpillars, as one has observed, are 

 elegant and beautiful. I shall, for a taste of the rest, describe 

 one of them ; which I will, some time the next month, show 

 you feeding on a willow-tree ; and you shall find him punc- 

 tually to answer this very description : his lips and mouth 

 somewhat yellow ; his eyes black as jet ; his forehead purple ; 

 his feet and hinder parts green ; his tail two-forked and black ; 

 the whole body stained with a kind of red spots, which run 

 along the neck and shoulder-blade, not unlike the form of St. 

 Andrew's Cross, or the letter X made thus crosswise X, and a 

 white line drawn down his back to his tail ; all which add 

 much beauty to his body. And it is to me observable, that at 

 a fixed age, this caterpillar gives over to eat, and towards 

 winter comes to be covered over with a strange shell or crust 

 called an aurelia and so lives a kind of dead life, without eat- 

 ing all the winter. And as others of several kinds turn to be 

 several kinds of flies and vermin the spring following, so this 

 caterpillar then turns to be a painted butterfly." 



The two-forked tail alluded to, which is peculiar to the 

 Puss-Moth larva and two or three others, is thus described by 

 Kirby and Spence (Introduction to Entomology, iii. p. 150) : 



"This horn-like appendage is composed of two distinct 

 cylindrical diverging branches, each about four lines long, not 

 united at the base. Each of these is hollow, and includes a 

 smaller cylindrical piece, which can be protruded at pleasure, 

 and withdrawn again, as a pencil within its case ; or, rather, as 

 the horns of a snail. The two outer horns are tolerably firm, 

 movable at their base, and beset with black spines ; the in- 

 terior tentacula are fleshy, movable in every direction, and in 

 full-grown larvae of a rose-colour. The animal seldom protrudes 

 them, unless in some way disturbed ; and frequently it approxi- 

 mates the outer cases so closely that they resemble a single 

 horn. It appears to use these inner horns, when protruded, 



