TREMATODES FROM FISHES — CLINTON 151 



maximum breadth, 0.9 mm. ; necklike portion at anterior end, length, 

 6.5 mm.; breadth, 0.45 mm.; diameter at anterior end, 0.33 mm.; 

 diameter of oral sucker, 0.26 mm. ; pharynx, length, 0.21 mm., breadth, 

 0.15 mm.; ova, 0.014 by 0.011 mm. Worms from smallest cyst of 

 practically the same dimensions as those from largest cyst. 



Two cysts from one of three fishes examined August 18, 1903. 

 One fish examined on August 19, two on August 20, and one on 

 August 24; no cysts found. Length of cyst, 10 mm.; diameter, 3 

 mm. Two worms from each cyst, measuring 50 nun. in length in sea 

 water. Walls of cyst transparent ; color of worms yellow, due to ova 

 in the voluminous folds of the uteiiis ; neck translucent, bluish-white, 

 traversed by a yellow line, the metraterm. Measurements, life : Oral 

 sucker, length, 0.17 mm., breadth, 0.20 mm.; pharynx, length, 0.17 

 mm., breadth, 0.15 mm. Three cysts from gills, two worms in each 

 c)-st, collected by Vinal N. Edwards September 22, 1903. 



Six cysts from gills, collected June 17, 1904, by Vinal N. Edwards ; 

 long oval-elliptical, length 10 mm., diameter, 3.5 mm. 



Cysts from gills. Edwards examined the gills of 100 bonitos on 

 August 31, 1904, and found about 10 out of every 12 infected, with 

 2 and 3 cysts on each infected fish. 



One cyst collected July 8, 1905, from gills containing two worms, 

 one 50 mm. in length, the other slightly less. 



Gills of bonito were examined on six dates, August 10 to 27, 1906, 

 no cysts found. 



Three cysts from gills (U.S.N.M. No. 8387), two worms in each 

 cyst, collected August 3, 1908. These were younger stages than any of 

 those hitherto recorded. One of them was examined while it was still 

 active. Length of esophagus about 2.5 mm.; intestinal rami extend 

 to the posterior end, and in places contained orange-colored granular 

 material. The anterior end of the uterus, metraterm, was nearly 

 straight, lay beside the esophagus and opened at the junction between 

 the oral sucker and pharynx ; ova, 0.014 by 0.009 mm., yellowish, but 

 with moderately high magnification, both by transmitted and reflected 

 light, they appear to be faintly gi'eenish. In another specimen, 

 length, 18 mm., neck slender, length, 3.5 mm. ; anterior end white, re- 

 mainder of body lemon yellow, due to ova ; rami of intestine con- 

 voluted; neck very contractile; oral sucker and pharynx each oval- 

 elliptical in outline, and of about the same size, 0.015 to 0.016 nmi. in 

 diameter; neck very changeable, varying in diameter from 0.2 to 0.7 

 nmi. ; movements of body back of neck very slight ; diameter of bodj^ 

 from 0.8 to 1 mm., tapering to posterior end. In another specimen 

 the pharj'nx was much smaller than the oral sucker and appeared to 

 be rather thin-walled and collapsed. In this specimen the neck was 

 contracted so as to throw the esophagus into a number of crowded 



