394 



TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



previous two days in darkness, the corresponding figures 

 are 8'81 and 8'96 milligrams at the commencement, and 

 4'71 and 5'85 milligrams at the end, corresponding to an 

 average consumption of 165 milligrams of oxygen. This 

 illustrates the rate at which the marine plant can 

 synthesise, for the dried weight of vegetable matter inside 

 could certainly not have exceeded 1 gram. The experi- 

 ment was then continued in darkness, after a day's pause 

 to weigh and attempt feeding the animal. No food was 

 taken, however. The weight of the animal was 205 grams, 

 as against 203 grams at commencement, and this after 

 26 days practically without food. 











Oxygen appearing 

 in Carbon-dioxide. 







Oxygen used 



up. 



Date. 



Time 



, * — 





t 



: > 





Interval. 



Milligrams 

 per litre. 



Total 



Milligrams 



Total 





h. m. 



mg. 



per litre. 



mg. 



September 7-8 . 



. 23 55 



2-60 



118 



4-2 



191 



8-9 . 



. 23 20 



3-97 



181 



3-8 



173 



9-10 . 



. 23 50 



311 



142 



2-9 



132 



10-11 . 



. 23 45 



3-34 



152 



3-5 



159 



11-12 . 



. 23 50 



3-19 



145 



4-8 ' 



219 



12-13 . 



. 23 55 



3-85 



176 



3-8 



174 



Experiment finished. Weight of animal, 210 grams, 

 that is, 7 grams more than at the beginning of the 

 experiment. It is to be remembered in this connection 

 that this was not a fully-grown lobster, yet the result is 

 interesting. The explanation probably lies in this, that 

 the exo-skeleton continued to grow, and the tissues became 

 less rich in organic substances. The animal was placed in 

 absolute alcohol, and later the proteins, fats, and carbo- 

 hydrates of the body were estimated, with results to be 

 described later. 



So far as we have been able to ascertain, this is the 

 longest experiment yet made on the respiratory exchanges 

 of a large crustacean, with daily determinations of the 

 amount of oxidation. Perhaps the most interesting result 

 is the slowness of oxidation and the correspondingly small 

 amount of food required for the actual metabolic wants 



