j0g£ J Hakek. The S't\jaHm\.'ii\n of Stones by .inimals 85 



A. M. Recce (1915), in his treatise "The Alligator and its Allies", cites 

 gastroliths of from two to three centimetres in diameter as being found in 

 the stomach of a crocodile from Madagascar. Also, "in an alligator thirty 

 inches long, were fourteen pebbles of irregular size, varying from four to 

 seven mm. in diameter, and aggregating six grammes in weight". 



Present day crocodile hunters in the north of Australia have also recorded 

 atones in the stomachs of these saurians. Peter Lyell (1950). in ll'ild Life. 

 records that: Two cupped handfuls of stones (from the river bed I is the 

 average quantity inside an ordinary-sized crocodile. 



S. \V. Williston (1918) gives a more humorous aspect of crocodiles 

 swallowing stones; in his book. Water Reptiles of Past, he mentions "an 

 old myth, that the crocodile of the N'ile swallows a pebble on each of its 

 birthdays, so giving the Arabs reliable information of its age by the number 

 of *tones in its stomach". 



Lizards, also, have attained a reputation tor swallowing stones. K. I„ 

 Moodie, writing in Seiejiee (1912). records that a living horned toad 

 ( I'hryiwstiui cornutum Harlan), collected in the Magdalen Mountains of 

 Xew Mexico, had "in its stomach twenty large somewhat abraded stones 

 of a rock which resembled lava; some of the stones were large for the size 

 of the animal, measuring nearly one-third of an inch in diameter. There 

 were also in the stomach about 200 red ants. The animal had undoubtedly 

 picked up the stones with the ants, and the association was probably 

 accidental". 



G. R. Wieland (1900) also mentions that lizards in captivity swallow 

 stones from the floor of their cages. 



Living Mammals 



We g<> now to the pinnipedia, where the records are all from living; 

 animals. In the report on seals of the Challenger Expedition (1887) \V. 

 Turner states that "the dried specimen of a seal's stomach from the Cape 

 of Good Hope, often referred to by fishermen and whalers as the "seal's 

 ballast bag', contained upwards of twenty smooth pebbles, flattened at the 

 sides as if by mutual attrition. 



'"They vary in size; one of the largest is 1J inches in its long diameter, 

 and there are several of equal dimensions, but the smallest is not much 

 smaller than a coffee bean. 



"Captain Henry Pain, when writing of the sea-lion, says that he has 

 seen upwards of twenty-five pounds weight of stones, some of which were 

 the size of a goose's egg, in a 'pouch' inside the animal, obviously the 

 stomach." 



In Allen's History of the Xorth American P'tkuipeds. (1880) \Y. D. 

 Klliot relates that he has opened the stomach in many specimens of 

 L'ollorhinus ursinus, and that in the old bulls he has seen stones which weigh 

 half a pound, and in one stomach he found about five pounds of pebbles. He 

 also possesses the stomach of a sea-lion in which more than ten pounds of 

 stones were present, some of which weighed two and three pounds. 



Robert Brown, in his account of the "Pinnepedia of the Greenland Seas" 

 (1868), states that he has often seen small stones or gravel in the stomach 

 of the walrus, and that this is a habit which it possesses in common with 

 the seal (Pfafiru l>arbata) and even the whale (Behtfia eatadon). 



Further records of stone swallowing by pinnepeds is given by K. O. P-mery 

 (1941), who "examined the stomachs of eleven dead sea-lions which had 

 drifted up on beaches near La Jolla, California. Although most of the 

 stomachs were empty, one contained a single flat pebble of sandstone, and 

 another had twenty-seven pebbles, mostly of wave-rounded Black Mountain 

 metavolcanics and a Jew of shale. Both these types of rocks are available on 

 the beaches near La Jolla. Because of the angularity and fragileness of the 



