Chap. V. AND DENUDATION. 2i7 



manner as gallinaceous and struthious birds 

 swallow stones to aid in the trituration of 

 their food, so it appears to be with terricolous 

 worms. The gizzards of thirty-eight of our 

 common worms were opened, and in twenty- 

 five of them small stones or grains of sand, 

 sometimes together with the hard calcareous 

 concretions formed within the anterior cal- 

 ciferous glands, were found, and in two others 

 concretions alone. In the gizzards of the 

 remaining worms there were no stones; but 

 some of these were not real exceptions, as 

 the gizzards were opened late in the autumn, 

 when the worms had ceased to feed and their 

 gizzards were quite empty.* 



When worms make their burrows through 

 earth abounding with little stones, no doubt 

 many will be unavoidably swallowed ; but 

 it must not be supposed that this fact 

 ; ccounts for the frequency with which stones 

 ; nd sand are found in their gizzards. For 

 1 eads of glass and fragments of brick and of 

 i ard tiles were scattered over the surface 



* Morren, in speaking of the earth in the alimentary canals of 

 worms, says, " prsesepe cum lapillis commixtam vidi : " ' De 

 i umbrici terrestris,' &c, 1829, p. 16. 



