Chap. 31.] Gizzard m Fowls. 315 



voured by two fpecies of infects, not part of them 

 picked out from other parts, but the whole entirely, 

 without leaving a veftige of any the lead pare of the 

 cantharis undevoured. Dr. Fordyce has procured 

 thefe infecls from chdfts of cantharides, imported from 

 Sicily, and which had lived upon the cantharis for fe- 

 veral months. After being wafhed with water fliglitly, 

 thefe infecls have juices perfectly bland, fo that if they 

 are bruifed and applied to any the mod tender and fen- 

 fible furface of the human body, they produce no in- 

 flammation, nor is there any appearance of their pof- 

 femng any matter having a ftimulating quality. 



There are two 'different proceffes, which in general 

 feem efTential to digeftion - } viz. trituration and the 

 action of a certain fluid or menftruum. All quadru- 

 peds are furniihed with teeth, by which they in ibine 

 meafure deftroy the texture of their food before it 

 pafles into the ftomach. The inftrnment of trituration 

 in granivorous fowls, and which anfwers the purpofes 

 of the teeth of quadrupeds, is the gizzard, through 

 which all their food paries, before it enters the organ, 

 which may properly be denominated their ftomach. 

 Among fowls, however, there are fome which have 

 a ftomach purely membranous, as the eagle, the hawk, 

 and birds of prey in general. Thefe have neither 

 gizzard nor teeth, but they are furnimed with a fharp 

 and crooked beak, which, by tearing their food to 

 pieces, ferves in fome meafure to prepare it for the 

 action of the other inftrument of digeftion, a fluid 

 endued with peculiar^ qualities, and which, as far as 

 our obfervations extend, feems to be in common to all 

 animals. 



The gizzard is an organ compofed of very thick 

 and ftrong mufcles ; it is lined internally with a fub- 

 ftance fo thick and callous as not to be hurt by grind- 

 ins: 



