142 NOTES TO THE 



digestion by these humble and hitherto unappreciated fellow- 

 labourers with farmers to ameliorate the condition of the earth's 

 surface, and to adapt it to the production of grass, food for the 

 higher animals. Thus the whole of the earth which forms a 

 rind of turf has again and again passed through the entrails of 

 the successive generations of earth-worms. A check upon the 

 too great increase of earth-worms is afforded by their being the 

 food of birds and moles. See also Literary Gazette, Nov. 25 

 1857." 



The earth-worm is admirably adapted by its structure for 

 tunnelling in the earth, and its wonderful borings are often 

 laid bare in the railway and other cuttings. When we consider 

 the great pressure of earth, besides its solidity, through which 

 these worms have to bore, it seems surprising that their delicate 

 organisms should not be crushed. The body is made of a number 

 of small rings, which are armed with short, stiff, harsh bristles, 

 by means of which they pull themselves along. As the sea- 

 mouse has brilliant hairs, and the Cape mole has lustrous fur, 

 so the earth- worm's cuticle has a shining, iridescent lustre, the 

 reason of which I am not in a position to explain. The nervous 

 and vascular system of the earth-worm is very complicated. It 

 lays eggs, for which the reader should look in decayed dung 

 heaps. The mouth consists of two small lips, the superior of 

 which resembles, in some degree, that of the Tapita. In the 

 Royal College of Surgeons, there is an admirable preparation 

 (No. 470) of the anatomy of the earth-worm. 



"The oesophagus, a wide membranous canal, is continued straight 

 down for half an inch, and ends in a delicate bag, or reservoir ; 

 to this succeeds a muscular stomach, or gizzard, disposed in the 

 form of a ring. The intestine is constricted at each segment of 

 the animal by a series of ligaments or partitions connecting it 

 to the parietes of the body, and swells out in the intermediate 

 spaces when distended by the particles of earth." 



Mr. Davy informs me that common snails are very palat- 

 able food for hungry people. Cut off the point of the 

 shell and pick them out with a pin like a winkle; put 

 them in salt and water for an hour. In winter they are 

 capital eating. They should be boiled in milk, but are very 

 good when eaten raw. Snails are used by hundredweights in Lon- 

 don and the provinces for feeding thrushes and blackbirds ; the 

 men collect them in market-gardens and hedgerows. They are 

 sold wholesale at 2$d. to M. per quart ; there are about five dozen 

 in a quart. Birds won't eat water-snails ; they are too sloppy ; 

 there is no body in them. No small bird eats the black and 



