I 



APPENDIX. 323 



reproduce the accidentally amputated head. — Quatrefages in Ann. 

 des Sc. nat. ii. p. 100 (1^44). 



The Earthworm moves along the surface, or in the soil, by alternate 

 elongations and contractions of a determinate portion of the body. 

 Stretching forward the anterior extremity to the utmost, it is then 

 fixed against the ground by means of the lateral bristles, and now 

 the rest of the body is drawn to the fixed point. It can move 

 backwards or forwards with nearly equal facility ; and when seized 

 in its progress, it wriggles and twists itself into many coiled knots 

 and circles. This it does also when wounded ; and its writhings 

 surely indicate a severe degree of suffering in the poor worm, 

 which is too often wantonly trodden upon. The movements of 

 the Earthworm in its burrow are performed with much greater 

 rapidity than on the surface, a superiority which results from the 

 disposition of the bristles along the sides ; for in a circular tube alone 

 can they all be brought into action and made to act as fulcra, the 

 animal having the power of protruding them to a slight extent. 

 Hence we find that the hole of the worm is of the same figure as its 

 body, and nearly of the same calibre, that the ascent and descent 

 may be retarded neither by over-straightness, nor by a wideness which 

 would render the contact of the bristles against its walls impossible. 

 The holes are in general sinuous, and worked in an oblique direction, 

 and lined with the slimy juice which exudes from the skin. They 

 vary in depth from a few inches to upwards of 4 feet, and have two 

 or, occasionally, several apertures, of which one is the vent, whence 

 they eject those vermicular pellets of earth that have passed through 

 the intestine, and are in fact moulded and fashioned within it. 



The mode in which the Earthworm burrows is this : — The ante- 

 rior extremity of the worm forms a cone, gradually tapering from, a 

 little in front of the belt to the snout, which is formed by the upper 

 lip being somewhat elongated over the mouth, like a short proboscis. 

 As this can be shortened and thickened or made gracile and sharp 

 at will, we can understand its fitness as an auger, and its equal apt- 

 ness for making a hole rather larger than the body when relaxed and 

 undistended. Wishing to burrow, and having selected a soft moist 

 earth, the worm stretches forward this anterior portion of its body 

 and stiffens it. It now pouts out the upper lip, and rendering it, 

 too, tense and elastic, the worm pushes it under the soil or clod, 

 raises it, and casts it aside ; then again it digs and loosens another 

 portion of earth, until, by many repetitions and much patience, the 

 tunnel is insensibly yet speedily completed. As the worm swallows 

 the great proportion of the soil raised in the progress of the work, 

 nature has furnished it with no instruments for the removal of the 

 obstacle, such as have been given to many other boring insects. 



LUMBRICUS * (page 5 7) . 

 Besides the sexual pores, which in the i. terrestris are in the 



* '^ Lumbrici Latinis alubricitate dicti videntur." — Raius. Professor Duges of 



y2 



