PREFACE. 



Fourteen years having- elapsed since I first commenced the 

 study of the gapes in fowls, it cannot be asserted that the con- 

 clusions now arrived at are hasty and have not stood the test 

 of time and mature consideration. My first paper on the sub- 

 ject was read before the Buffalo Microscopical Club, November 

 nth, 1884. In 1886 I published a paper in the Bulletin of the 

 Buffalo Society of Natural Sciences, Vol. V., No. 2. The pres- 

 ent publication is a revision of that paper, with extracts from 

 articles written for various journals, and additional matter here- 

 tofore unpublished in regard to the life history of the parasite 

 causing the gapes. The illustrations are from drawings made 

 by Mrs. Helen M. Judd from microscopic slides. I send forth 

 this small pamphlet with the earnest desire that science and the 

 poultry and game bird raisers throughout the world may be 



benefitted thereby. 



H. D. WALKER. 

 Franklinville, N. Y., November, 1897. 



