INTERNAL PARASITES OF THE SEBAGO SALMON. I163 



Concerning the Baltic salmon, other fragmentary data are also on record. 

 Olsson (1867) reported Bothriocephalus prohoscideus Rudolphi as frequent in 

 Salmo salar both from fresh and from salt water during April and August. 

 Later the same author (Olsson, 1876) \\sX.&d Distomum appendiculaiuni Rudolphi 

 as frequent in Salmo salar during August. Again (1893) he reported Disioma 

 appendiculatum Rudolphi from the stomach as abundant in July. The material 

 came from the Baltic Sea and the Gulf of Bothnia. 



Hausmann (1897) lists from Salmo salar Distomum appendiculatum, D. ocrea- 

 ium, D. reflexum, and D. varicum. Among 20 specimens examined 13 only 

 were infested with trematodes. 



Mijhling (1898) records from Salmo salar in East Prussia six species of para- 

 sites, as follows: Boihriotcenia proboscidea, Apoblema appendiculatum, Echino- 

 rhynchus acus, Ech. jusiformis, Ech. proteus, and Ech. pachysomus. The first 

 two are very common, the others occasional. Ech. fusiformis is cited after 

 Neumann. 



G. Schneider (1902) reports the following data concerning salmon parasites 

 in Finland: A salmon i m. long, caught November 6, 1900, in the mouth of the 

 river, was infested with several hundred individuals of Bothriotcenia proboscidea 

 Batsch, which entirely filled the pylorus portion of the intestine and of the 

 pyloric cceca. Otherwise the intestine contained no parasites and no food. A 

 second salmon, investigated fresh July 2, 1902, had in the intestine the young 

 and adult Bothriotcenia proboscidea Batsch and one Echinorhynchus larva, which, 

 however, evidently came from fish that had been eaten. In the stomach of 

 this salmon he found Clupea sprattus Linnaeus [p. 18 the name is given as Clupea 

 harengus membras L.] and in the intestine remains of digested fishes, probably 

 also herring. The synchronus presence of herring remains and of very young 

 Bothriotcenia in the intestine of this salmon confirms fully his formerly expressed 

 opinion that the salmon infects itself with tapeworms through eating the 

 herring. 



According to Schneider (1902, p. 20), Kessler in a Russian paper reported 

 the occurrence of adult Bothriotcenia proboscidea in the intestine of Salmo salar 

 from Lake Onega. This body of water is directly connected with the Baltic 

 Sea, where, according to Miihling, as just noted, this species is a very common 

 parasite of the salmon. vSchneider has also found it abundant in salmon from 

 the Gulf of Finland. 



No doubt some observations have been made on the parasites of salmon in 

 the Scandinavian peninsula, but they have thus far eluded my search. 



Concerning the parasites in the British Isles many observations are on 

 record. But they concern individual investigations at particular locations, and 

 as a rule do not cover any continuous study of the problem. In consequence the 

 lists are not as complete as those already cited for the Rhine and the Baltic, 



