KEPOBT OF THE VETEKENAKIAIS". 



To the Director of the Michigan Experiment Station : 



Sir — Since submitting my last report I have devoted considerable time to 

 the study of micro-organisms, observing their development and other 

 peculiarities. While watching the changes that occur in certain animal 

 excretions when exposed to ordinary atmosphere, I was one day engaged 

 making an examination of the faeces of a horse with the aid of a microscope, 

 when I was somewhat surprised to find an exceedingly lively little creat- 

 ure, performing very energetic serpentine movements in the field of the 

 instrument. 



I followed the above exhibition up by making daily examinations of the 

 excretions of the horse from which the specimen was obtained, and in nearly 

 every instance where the examination was made, I found a variable number 

 of immature whip-worms (oxyuris curvula), for such they proved to be. In 

 one instance I counted thirty-four wriggling in a field only one-twentieth of 

 an inch in diameter, showing that they might readily infest the intestines 

 in countless millions without being observed by ocular examination, unaided 

 by a magnifying power. 



On measuring one of the little creatures, I found it to be the one-sixtieth 

 part of an inch long, and about the one ten-thousandth part of an inch in 

 diameter; so we see why it would be next to impossible to discover their pres- 

 ence in the fasces by the unaided eye. 



On inquiry into the history of the horse from which these worms were 

 obtained, I learned that it was subject to frequent attacks of a disease known 

 as spasmodic colic, and that the attacks came on, from time to time, with- 

 out any apparent cause. With this account of the animal, I told the groom 

 to watch the horse carefully to see if it passed anything of an unusual 

 nature along with its faeces; but was not surprised some time afterwards at 

 being told that everything appeared to be all right, as far as the appearance 

 of the faeces was concerned, but that once in a while, besides the colic, there 

 was a tendency to diarrhoea. After watching this case for some months, I 

 concluded that the enteric irritation was due to these invisible parasites, and 

 treated the horse accordingly. 



With this case before me, I concluded to examine the faeces of horses 

 affected with colic — that is, when the symptoms are produced without any 

 apparent cause — and have been gratified to find in those cases that I exam- 

 ined with the microscope all showed plainly the presence of the immature 

 worm. I regret somewhat that I have not been able to examine the faecal 

 matter of a greater number of horses, but this, no doubt, will be done in 

 course of time, as I do not intend to lose sight of what has already been 

 brought under my notice; besides, the examination is so easily made, that I 



