42 "Worms, 



to observe) a visible decrease of those morbid symptoms, which arc 

 usually, though not constantly attendant, upon their presence. 



The Ascaris, as it is by much the most common, so it is also by 

 far the j^reatest enemy to the Horse. Usually too, its presence in 

 the Bowels may be confidently predicted, by a peculiar appearance 

 at the verge of. the Anus, very much resembling that of dried cream. 

 I do not recollect that any writer has attempted to account for this 

 very peculiar appearance, although I have heard it maintained that 

 it is owing to some cxcrementitious discharge of the Ascari«. I am 

 inclined, however, to suspect that it proceeds from a morbid secretion 

 of the Mucous Coat of the Rectum, arising from the stimulus 

 of the Ascaris near the Sphincter, It is but of little conse- 

 quence however to ascertain this speculative point, in comparison 

 of another of much greater importance in practice, which is_, 

 that the appearance I have alluded to, is by no means a constant 

 one, in all cases of the Needle Worm. And therefore, altliough we 

 should be perfectly safe, in laying it down as an axiom, that it is 

 never observed unless the Ascaris exist in the Bowels ; yet the con- 

 verse of the proposition, will not necessarily hold good, for it is by 

 no means uncommon, to find immense numbers of these Worms, 

 voided by Hprses, which exhibit none of the peculiar appearance 

 that has been described. Commonly, however. Horses affected with 

 Needle Worms, exhibit symptoms, though not so palpable, yet not 

 much less decisive of their presence than that which I have described. 

 For it mostly happens, that the Coat stares and looks unhealthy, tliat 

 the Animal loses his appetite, becomes dull and dispirited, and in a 

 more remarkable degree hide-bound, than I have ever observed to be 

 the case, in instances of the Round Worm. For Horses labouring 



