I092 BULLETIN OF THE BUREAU OF FISHERIES. 



chiefly due to parasitic worms, entozoa. From their omnivorous habits the 

 fish are especially subject to these. About 40 per cent of the 48 examined by 

 Professor Binford in 1908 were infected with AscaHs. Linton (1905) in his 

 "Parasites of the Fishes of Beaufort" reports the examination of 135 toadfish. 

 From these he obtained more than 190 nematodes, about the same number of 

 cestodes, and more than 100 trematodes. The nematodes are all of one species 

 (Ascaris habena), the cestodes of five genera and as many species, and the 

 trematodes (so far as identified) of three genera and three species. Examina- 

 tion of Linton's other publications will show that toadfish in other localities 

 are similarly infested. 



In the course of this research it was not infrequently noticed that some of 

 the toadfish kept in confinement had "pop-eye." Whether these fish were thus 

 affected when captured, or whether the trouble originated in confinement, can 

 not be stated, but it should be noted that other fish, kept in the same tank at 

 the same time, and large numbers of various kinds of fishes kept in running 

 water under the writer's care during the five preceding summers, showed no 

 symptoms of this disease. 



Direct evidence is at hand, also, to show that wild fish have the same trou- 

 ble. On July 7, 1907, there was taken in the trap hung off the wharf a large 

 toad which had either the conjunctiva or cornea " of its eyes enormously dis- 

 tended, projecting one-half to five-eighths inch in front of the iris. One other 

 fish caught at the same time showed a slight distension of the eye covering, 

 while others had eyes perfectly normal in this respect. Pressure applied by 

 means of a pencil to the eye showed that whatever caused the distension gave 

 the membrane great firmness. Neither the distension nor the pressure of the 

 pencil seemed to cause the fish discomfort, for only after an appreciable length 

 of time did he move away, and then in an undisturbed manner. This was not 

 that form of exopthalmia in which the whole eye is pushed out of the socket. 

 The distending substance was evidently between the eye proper and its outer 

 covering. 



On July 10, 1907, two fish were taken from the trap at the wharf. Both 

 these had their caudal fins blood red in those parts where the pigment was not 

 so dense. Whether or not this indicates disease the writer can not say, but it is 

 not an altogether uncommon phenomena among fishes, as he has noticed it in 

 other forms, Lepisosteus, for example. At the time it was thought that maybe 

 it indicated sexual maturity, as noted in Lepidosiren by Kerr (1900), and 

 dissection showed that one, a male, was breeding, while the other, a female, 

 had eggs nearly ripe enough to flow from the ovary. 



o 1 unfortunately did not dissect to ascertain which. 



