280 Account of a Filaria in a Horse^s Eye. 



fusion of coagulable lymph, the result of inflammation of the 

 vessels^ caused by the presence of a foreign body. There is no 

 doubt whatever that the discoloration exists in the aqueous hu- 

 mor, and not in the cornea. A few weeks after the animal was 

 first discovered, the conjunctiva was much injected; but since 

 that time it has assumed its natural, healthy appearance, and now 

 does not differ in the least from that of the other eye. There is 

 nothing peculiar in the appearance of the horse, which is of the 

 Eclipse family, and seven years old. Owing to the incessant and 

 rapid motion of the worm, it is difficult to examine it with a mi- 

 croscope, so as to determine with accuracy, its precise internal 

 organization, yet it evidently belongs to the class Entozoa, order 

 Nematoidea, genus Filaria, species Papillosa. The only oth- 

 er genus which it resembles, is the Gordiiis of Linnasus ; but 

 as this belongs to the class Annelides, which have red blood, in- 

 habit the water only, and are more filiform in shape, there is but 

 little danger of confounding them together. 



We have stated that the Entozoa are so called because they 

 inhabit the interior of other animals. Every kind of animal, in- 

 deed, has been supposed to have its Entozoa, or internal parasites, 

 which are peculiar to itself, just as it has its Ectozoa, or external 

 ones. They not only infest the alimentary canal, and the ducts 

 leading into it, but also the muscles, the cellular tissue, and the 

 parenchymatous structure of the different organs, as the brain, 

 liver, lungs, kidneys, &c. Indeed, it is now believed by many 

 naturalists, that every difi'erent tissue and organ of the body has 

 its peculiar parasite. Thus in man, more than twenty different 

 species of animals have been discovered in different parts of his 

 body. In the brain, we find the Echi?iococus hominis ; in tiie 

 liver, the Fasciola hepatica ; in the vetious blood, the Linguatu- 

 la venarum ; in the kidneys, the Strongylus gigas ; in the tnus- 

 cles, the Hydatigera celhilosa ; in the cellular tissue, the Filaria 

 gnedinensis, or Guinea worm ; in the female ovai^ies, the Lingua- 

 tula pinguicola ; in the intestines, the Tmiia solium, the Ascaris 

 lumbricoides, &c. ; and some attack infants only, as the Oxyurus 

 vermicularis. 



Mr. Richard Owen, of England, has lately discovered that the 

 human muscles of voluntary motion are sometimes the residence 

 of very minute cysts of an oblong figure, in size and color bear- 

 ing a strong resemblance to nits, or the young of pediculi. 



