518 
HENRY LESLIE OSBORN 
system, Lake Chautauqua being at the head of one of the tribu- 
taries of the Ohio River. 
The worm has also been recognized by me in the rock bass 
from Lake Chautauqua occurring in the same way as in the black 
bass. I have also at Lake Chautauqua found that many of the 
small fishes are more or less infected with small black spots in 
the skin, both of the general surface and especially in the membrane 
on the fins. In one instance the pectoral fin of a small sun fish 
exhibited a small white cyst in the membrane between the fin 
rays. A drawing of this was made at the time and from this fig. 
7 has been copied. It contained a living immature individual 
which is adequately shown by its two ventral suckers to be iden- 
tical with the species now under consideration. 
In the chyle in which this worm was found there are generally 
two other distomes : a species of Bunodera since described as new 
and designated B. corniitum (Osborn '02) and an immature and 
undetermined fluke whose genital organs are sufficiently developed 
to locate the reproductive opening at the posterior end, thus 
placing it with the Urogonominae. These latter were traced back 
to black colored cysts found in the fins and skin of smaller fishes. 
In the masses of slime in which Cr3^ptogonimus and these other 
flukes occurred, I found in one instance the remains of vertebral 
centra of a small fish. This justifies the inference that the worm 
reaches the bass, its definitive host a predaceous fish, by way of 
the smaller fishes, and suggests that the search for the unknown 
primary host of Cryptogonimus will have to be made among the 
animals which serve as food for the small fishes. 
My notes of observation on the living wo:rms contain very little 
on outward movements. They were removed from the chyle in 
which they were found and watched in salt solution. Under this 
condition many flukes are \ery active. I have given elsewhere 
('04) an account of the movements of Cotylaspis insignis. Cryp- 
togonimus under this condition lies nearly motionless with the 
ventral surface up most of the time. Occasionally the worm 
turned over but soon returned to its inverted position. The only 
general bodily movements were an elongation of the anterior 
end and its retraction, but no movements of locomotion were 
