JUL 1 1BS8 



AN UNUSUAL PHYTO-BEZOAR. 

 William Trelease. 



In January, 1897, Dr. Francis Eschauzier, of San Luis 

 Potosi, Mexico, sent to me two specimens (Plate XL.), one 

 a ball of surprising accuracy of surface, measuring a little over 

 three and one-half inches in diameter and weighing seven 

 and one-half ounces, and the other one-half of a similar ball, 

 about four inches in diameter and weighing four ounces, — 

 stating that sixteen such balls of about the size of the speci- 

 mens sent had been taken from the stomach of a bull at the 

 Hacienda de Cruzes, and adding that he believed them to be 

 composed entirely of an agglomeration of the fibers of some 

 cacti, an undigested portion of which formed the nucleus. 

 Subsequent inquiry resulted in the additional information that 

 the chief food of cattle at that season of the year consisted of 

 five Opuntias, and that the animal from which the specimens 

 were obtained was wild, of fighting stock, and consequently 

 allowed to seek food where it could be found, instead of 

 beino- fed upon cacti which had been roasted, as is the custom 

 with other stock. My informant further stated that the wild 

 bulls drink very little water while feeding upon cacti, and that 

 the animal in question, which was ten years old, had not 

 exhibited any signs of illness, though for some time the large 

 size of its abdomen had attracted the attention of the 

 vaqueros, but, owing to the intractability of the animal, no 

 examination of it could be v made until after its death. 



The specimens, which were exhibited to the Academy Feb. 

 15, 1897, are of a brown color, and in appearance some- 

 what suggest felt or rubbed sole leather, and on examination 

 prove to be composed, aside from the small nucleus at the 

 center, of the barbed hairs with which the pulvini of the Pla- 

 topuntias are armed. To the barbs with which these hairs 

 are covered is due their power of felting together, and there 



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