bath for three hours; the glycogen was then precipitated with alcohol, washed, and converted into glucose, which was estimated by Fehling's method.

Fat was estimated by Rosenberg's method—i.e., extraction of the dried material with boiling absolute alcohol and chloroform alternately, with subsequent ether extraction of the material so obtained.

Protein was calculated from the amount of nitrogen on the assumption that the nitrogen formed 16 per cent. of the molecule. It was recognized, of course, that all the nitrogen present was not in the form of protein—in fact, oysters owe much of their value in dietetics to the presence of nitrogenous extractives; on the other hand, they contain much nucleo-protein, or a similar body rich in phosphorus, in which the nitrogen must be under 16 per cent.

Ash or mineral matter was estimated by incineration, aided by extraction with hot distilled water and subsequent evaporation of the extract.

The results are given in Tables I and II.

In the above table it may be observed that samples I, II, and III were obtained early in the season, sample IV at the end, and on comparing these it is evident that a marked deterioration of the oyster occurs by the end of the season: it becomes more watery, glycogen drops to one-seventh of its initial value, the fat diminishes to nearly half, and the extractives are relatively increased. It would be interesting scientifically, and would throw a valuable light on what ought to be the limits of the oyster season in New Zealand, if analyses were made at regular and frequent intervals throughout the year.

From Table II it will be seen that at their best the New Zealand oysters contain much less glycogen and relatively more fat than the average American oyster.