128 FIELD AND FOREST. 



pecialy tenacious: over the segments proper, the areolar tissue is dense 

 and abundant 



If, with a strong-pocket lens, we look directly down upon the sides 

 and ventral surface, there are visible, projecting from almost circular 

 openings in the skin, and pointing backward, eight lines of glistening 

 bristles, beginning at the very first segment (considering the first seg- 

 ment to be the one immediately behind the two lips), and extending 

 in unbroken order to the very last. These setae are arranged in pairs 

 forming four continuous rows, of four sets and eight bristles to every 

 segment. In the central and terminal rings they are frequently ac- 

 companied by several aciculi, at times short, broad, and sharp, at 

 others long and narrow. The worm has not only the power to pro- 

 ject them from their proper openings, but to entirely withdraw them 

 into the cavity of the body. 



Contained as each seta appears to be, in a sheath, structureless and 

 apparently identical in character with the skin, it is an object of inter- 

 est, but when isolated it becomes a thing of beauty. The free end is 

 roughened by friction against the earth, it is translucent, and its gene- 

 ral outlines are of the most graceful form. I suppose when Hogarth 

 drew his celebrated line of beauty, the thing most remote from his 

 thoughts was an earthworm, but if he had prepared a line with the 

 curves of an earthworm's bristle and named it the line of beauty, the 

 difference between it and his original creation would have been slight. 

 There is nothing new under the sun, the wise man said; the very line of 

 beauty was hidden in an earthworm's skin when the great artist's pencil 

 was making an unsuspected copy. These bristles, at every step enable 

 the worm to put into practical use one of the first principles of me- 

 chanics — that of the lever; for not only do they by the aid of special 

 muscles, hold the distance gained b)- muscular contraction, but also 

 help by prying the body forward. 



But how does the creature progress? "O, it wriggles!" says a young 

 lady near by ; "or, if it doesn't wriggle, it hangs on with its mouth, and 

 in some way tucks up its tail !" She is a charming young lady, whose 

 explanation is very similar to that of a charming writer: none other 

 than the creator of the immortal Vicar of Wakefield. In his "Ani- 

 mated Nature '," Goldsmith says of the earthworm : "There is a spiral 

 muscle that runs round its whole body, from the head to the tail, some- 

 what resembling a wire wound round a walking-cane, which when slip- 



