Linton. — Fish Parasites and Public Health 25 



ous," "very numerous." In order to determine to which 

 column of the record the fish under examination should 

 be referred, the fish, having been split open with a sharp 

 knife inserted near the middle of the back, thus had the 

 flesh of one side separated from the skeleton. In many 

 cases only one or two cysts are found, and as these cysts 

 are only about one millimeter in the longest diameter, 

 careful attention had to be given in order to make the 

 record as exact as possible. Now the nematodes which 

 are of such common occurrence on the viscera of the 

 butterfish are about 12 millimeters in length, and are, 

 moreover, of a reddish brown color. They are therefore 

 much more conspicuous objects than the cysts, which 

 do not differ much in color from the muscles and bones 

 with which they are associated. If nematodes were at 

 all common in the flesh of the butterfish, therefore, they 

 would most certainly have been detected in this search 

 which began in the summer of 1904 and has been con- 

 tinued each season since. Most of the examinations were 

 made in the months of July and August. These are sup- 

 plemented by examinations made by Mr. Vinal N. Ed- 

 wards in the months of May, June, September and Octo- 

 ber. The examinations were made on different dates 

 throughout the season. Thus my record shows that in 

 the season of 1912 there were 948 butterfish examined 

 for flesh parasities on 23 dates in July from the 4th to 

 the 31st, and on 10 dates in August from the 1st to the 

 23d. In 1913 butterfish were examined on 30 dates from 

 June 30th to August 29th; in 1914, 785 were examined 

 on 32 dates from July 10th to September 9th. Besides 

 these I have records of examinations made by Mr. Ed- 

 wards of 416 butterfish on 21 dates in May, June, Sep- 

 tember and October. The total number of butterfish 

 which I have examined for flesh parasites in successive 

 years from 1904 to the present time is 5,992 ; in the last 

 eight years the smallest number for any one year is 416. 



Mr. Edwards reports that he has found no nematodes 

 in the flesh of butterfish. My own record of finds of 

 nematodes in the flesh of butterfish is as follows: On 



