Parasites,, Diseases and Enemies. 253 



or more on each side; nostril single median; mouth 

 sub-inferior, nearly circular, adapted for sucking; heart 

 without arterial bulb ; alimentary canal straight, simple ; 

 vertical fins with feeble rays. Naked eel-shaped ani- 

 mals found in all cool waters." 



Yet when I testified in court as to the species of eels 

 in our waters, I was followed by a man who claims to 

 be an authority on fishes, who mentioned the "lamper 

 eel" as an eel. Jordan says: "They attach themselves 

 to fishes, and feed by scraping ofif the flesh with their 

 rasp-like teeth." An exhaustive and well illustrated 

 paper on this subject may be found in the Bulletin of 

 the United States Fish Commission, Volume XVII., 

 1897, pages 209 to 215, by Prof. H. A. Surface, M. S., 

 Fellow in Vertebrate Zoology, Cornell University, 

 under the title of "The Lampreys of Central New 

 York." The illustrations show the lampreys, and 

 photos of pickerel, suckers and catfish with great holes 

 in their sides, where they had been eaten. Lampreys 

 have the habit of leeches. 



The same volume, pages 193, 199, contains an article 

 entitled "An Economical Consideration of Fish Para- 

 sites," by Dr. Edwin Linton, Ph. D., Professor of 

 Biology, Washington and Jefferson College. The 

 reader who wishes to pursue the subject further is rec- 

 ommended to get the volume named. 



In 1886 Mr. C. Van Beuren, President Balsam Lake 

 Club, Hardenburgh, Ulster County, N. Y., wrote me: 

 "A number of trout have been caught in our lake with 

 black spots on them. These spots are not very numer- 

 ous, perhaps a dozen on one fish, They are on the 

 back, sides, fins and tails, and they feel like shot under 

 the skin. We have examined the spots under a micro- 

 scope and find them, as viewed by the eye, to be 1-32 of 



