FUKGUS H^MAtODES. 173 



the jaw also. Dreadful cases of l fungus haematodes' 

 have arisen from the irritation of caries. 



"Every horse that gets thin or out of condition, 

 without fever or other apparent cause, should have his 

 teeth and mouth examined, especially if, without any 

 indication of sore throat, he * quids' his food ; or if he 

 holds his head to one side while he eats, in order to 

 get the food between the outer edges of his teeth. The 

 cause is irregular teeth. Such a horse is materially 

 lessened in value and is to all intents and purposes 

 unsound, for although the teeth may be carefully sawn 

 down, they will project again at no great length of 

 time. A horse cannot be in full possession of his nat- 

 ural powers without perfect nutrition, and nutrition 

 is rendered imperfect by any defect in mastication." 



Prof. R Owen, in his work entitled "A History of 

 British Fossil Mammals and Birds " (pp. 388-9), gives 

 an account of a diseased fossil horse's tooth which he 

 found at Cromer. He says he is " induced to cite one 

 of the curious examples of disease in an extinct animal 

 from the rarity of its occurrence in the tissue which is 

 the subject of it." The facts of this rare case are as 

 follows : 



" One of the Cromer fossil teeth, from the lower jaw, 

 with a grinding surface measuring one inch five lines 

 in long (antero-posterior) diameter, and eight lines in 

 short (transverse) diameter, presented a swelling of 

 one lobe, near the base of the implanted part of the 

 tooth. To ascertain the nature and cause of this en- 

 largement, I divided it transversely, and exposed a 

 nearly spherical cavity, large enough to contain a 

 pistol-ball, with a smooth inner surface. The parietes 

 of this cavity, composed of dentine and enamel of the 



