of the, Salmon in Fresh Water. 155 



Loss of Phosphorus by Muscle 3-740 

 Gain Testes 0-717 



Surplus 3-023 gnus. 



It would thus appear that the store of phosphorus in the muscle is 

 far more than sufficient to yield the phosphorus required in the con- 

 structive changes in the testes. 



It is interesting in this connection to note that in the male during the 

 summer months there is a great growth of bone in the snout, and it is 

 highly probable that some of the phosphates stored in the muscles is 

 utilised in this process. 



GENERAL CONCLUSIONS. 



These observations on the distribution and exchanges of phosphorus 

 in the salmon throughout its sojourn in fresh water show that a supply 

 of phosphorus, partly as inorganic phosphates, partly as lecithin, is 

 stored in the muscles as these grow and become loaded with fat during 

 the stay of the fish in the sea. 



While the fish is in the river this stored phosphorus is transmitted 

 from the muscle to the growing ovaries and testes, and in being trans- 

 mitted undergoes changes in its chemical combinations. In the ovary 

 the simple phosphates of the muscle are, (a) combined with fatty 

 acids and cholin to form the abundant supply of lecithin ; (6) combined 

 with proteids to form the pseudo or para nuclein ichthulin which is 

 so abundant a constituent of the ovary, (c) In the testes, on the 

 other hand, the phosphorus of the muscle phosphates is elaborated with 

 the more complex nucleic acid and combined with the characteristic 

 base protamin. 



The source of these two nitrogenous bases the cholin of the 

 lecithin and the protamin of the nuclein of the testes we do not at 

 present know. They must ultimately be derived from proteids since 

 these are the only nitrogen-containing constituents of the body, and 

 Miescher has suggested that the "albuminose" of the early testis is 

 the forerunner of the protamin of the ripe organ. 



There is no evidence that the transference of phosphorus from the 

 muscles to the genital organs is not direct. There is no evidence that 

 the liver plays any intermediate part. In fact, all the evidence tells 

 against such an idea. It is apparently in and by the active protoplasm 

 of the growing ovaries and testes that these profound chemical changes 

 are carried out. 



These observations indicate that from the simple phosphates of the 

 muscle, by synthesis, lecithin, the ichthnlin of the ovaries, and the nucleic 

 acid of the testes are all built up. That lecithin is a stage in the pro- 

 duction of the ichthulin of the ovary and nuclein of the testis seems to 

 be indicated first by its accumulation in the muscles, and second by its 

 appearance in both ovaries and testes. That it is a forerunner of the 

 nucleins and phosphorus compounds of the embryo is undoubted. 

 As to the source of the phosphorus stored in the muscle, there can be 

 little doubt that it is in great measure derived from the phosphates in 

 the bones of herring and other fish upon which the salmon feeds. Th<> 

 evidence is against the idea that the lecithin of the muscles is also direct !\ 

 taken from the lecithin in the food, for Hasebrock (Ztsch. f. phys. Chan., 

 Bd. XII., 150) has shown that in the intestine lecithin is split up into 

 glycero-phosphoric acid, cholin, and fatty acids. There must thus be 

 synthesis of this material in the body. 



