128 



Investigations on the, Life-History 

 TABLE VII. 



Showing balance of nitrogen between muscle and ovaries per fish of 

 standard length: 



These balances clearly show that the amount of proteid lost from the 

 muscle is ample to supply the wants of the growing ovaries, as in each 

 case the loss from the muscle is greater than the gain by the 

 ovaries. As previously stated, the surplus loss may be considered as 

 showing that there is a consumption of proteid to meet the other 

 requirements the production of energy and the repair of energy-pro- 

 ducing mechanism. It will be seen that this surplus loss amounts in 

 each instance to a very considerable quantity in one case to 22 grammes 

 of nitrogen per fish of standard length, in the other to 20 grammes. 



Twenty-two grammes of nitrogen are equivalent of 1 37'5 grammes of 

 proteid, the energy value of which is 560 large calories or 240,000 

 kilogramme-metres, an amount of energy sufficient to raise a fish of 

 standard length weighing 10 kilogrammes to a height of 2 4, 000 metres 

 (or 78,000 feet). Similar calculation shows the other suiplus loss has 

 an energy value of 2 1 7,000 kilogramme-metres, and is sufficient to raise 

 a fish of standard length to a height of 21,700 metres (or 71,000 feet). 



V. Conclusions. The inferences to be drawn from this examination 

 of the female fish of 1896 may be summed up as follows : 



1. Estuary fish have more muscle proteid than upper- water fish. 



2. The amount of muscle proteid in the upper-water fish diminishes 

 as the season advances. The October and November upper-water 

 fish are very poor in muscle proteid, having little more than half the 

 amount of muscle proteid that estuary fish have. 



3. The ovaries of both estuary and upper- water fish gain proteid as 

 the season advances. 



4. The estuary fish and the upper-water fish of the early months have 

 sufficient proteid in the musculature to supply the wants of the growing 

 ovaries, and from the deficit of muscle proteid found in the late upper- 

 water fish, it is probable that there is a transference of proteid from the 

 musculature to the ovaries. 



5. The deficit of muscle proteid in upper water fish is so large that 

 after allowing for the requirements of the ovaries there remains a surplus 

 loss. This surplus loss is available for the liberation of a large amount 

 of energy. 



MALE FISH, 1896. 



The examination of the male fish received during 1896 corroborates 

 the results obtained from the examination of the female fish of that 



